Merge branch 'master' of https://github.com/danvk/dygraphs
[dygraphs.git] / dygraph.js
1 /**
2 * @license
3 * Copyright 2006 Dan Vanderkam (danvdk@gmail.com)
4 * MIT-licensed (http://opensource.org/licenses/MIT)
5 */
6
7 /**
8 * @fileoverview Creates an interactive, zoomable graph based on a CSV file or
9 * string. Dygraph can handle multiple series with or without error bars. The
10 * date/value ranges will be automatically set. Dygraph uses the
11 * <canvas> tag, so it only works in FF1.5+.
12 * @author danvdk@gmail.com (Dan Vanderkam)
13
14 Usage:
15 <div id="graphdiv" style="width:800px; height:500px;"></div>
16 <script type="text/javascript">
17 new Dygraph(document.getElementById("graphdiv"),
18 "datafile.csv", // CSV file with headers
19 { }); // options
20 </script>
21
22 The CSV file is of the form
23
24 Date,SeriesA,SeriesB,SeriesC
25 YYYYMMDD,A1,B1,C1
26 YYYYMMDD,A2,B2,C2
27
28 If the 'errorBars' option is set in the constructor, the input should be of
29 the form
30 Date,SeriesA,SeriesB,...
31 YYYYMMDD,A1,sigmaA1,B1,sigmaB1,...
32 YYYYMMDD,A2,sigmaA2,B2,sigmaB2,...
33
34 If the 'fractions' option is set, the input should be of the form:
35
36 Date,SeriesA,SeriesB,...
37 YYYYMMDD,A1/B1,A2/B2,...
38 YYYYMMDD,A1/B1,A2/B2,...
39
40 And error bars will be calculated automatically using a binomial distribution.
41
42 For further documentation and examples, see http://dygraphs.com/
43
44 */
45
46 /*jshint globalstrict: true */
47 /*global DygraphLayout:false, DygraphCanvasRenderer:false, DygraphOptions:false, G_vmlCanvasManager:false */
48 "use strict";
49
50 /**
51 * Creates an interactive, zoomable chart.
52 *
53 * @constructor
54 * @param {div | String} div A div or the id of a div into which to construct
55 * the chart.
56 * @param {String | Function} file A file containing CSV data or a function
57 * that returns this data. The most basic expected format for each line is
58 * "YYYY/MM/DD,val1,val2,...". For more information, see
59 * http://dygraphs.com/data.html.
60 * @param {Object} attrs Various other attributes, e.g. errorBars determines
61 * whether the input data contains error ranges. For a complete list of
62 * options, see http://dygraphs.com/options.html.
63 */
64 var Dygraph = function(div, data, opts, opt_fourth_param) {
65 if (opt_fourth_param !== undefined) {
66 // Old versions of dygraphs took in the series labels as a constructor
67 // parameter. This doesn't make sense anymore, but it's easy to continue
68 // to support this usage.
69 this.warn("Using deprecated four-argument dygraph constructor");
70 this.__old_init__(div, data, opts, opt_fourth_param);
71 } else {
72 this.__init__(div, data, opts);
73 }
74 };
75
76 Dygraph.NAME = "Dygraph";
77 Dygraph.VERSION = "1.2";
78 Dygraph.__repr__ = function() {
79 return "[" + this.NAME + " " + this.VERSION + "]";
80 };
81
82 /**
83 * Returns information about the Dygraph class.
84 */
85 Dygraph.toString = function() {
86 return this.__repr__();
87 };
88
89 // Various default values
90 Dygraph.DEFAULT_ROLL_PERIOD = 1;
91 Dygraph.DEFAULT_WIDTH = 480;
92 Dygraph.DEFAULT_HEIGHT = 320;
93
94 // For max 60 Hz. animation:
95 Dygraph.ANIMATION_STEPS = 12;
96 Dygraph.ANIMATION_DURATION = 200;
97
98 // Label constants for the labelsKMB and labelsKMG2 options.
99 // (i.e. '100000' -> '100K')
100 Dygraph.KMB_LABELS = [ 'K', 'M', 'B', 'T', 'Q' ];
101 Dygraph.KMG2_BIG_LABELS = [ 'k', 'M', 'G', 'T', 'P', 'E', 'Z', 'Y' ];
102 Dygraph.KMG2_SMALL_LABELS = [ 'm', 'u', 'n', 'p', 'f', 'a', 'z', 'y' ];
103
104 // These are defined before DEFAULT_ATTRS so that it can refer to them.
105 /**
106 * @private
107 * Return a string version of a number. This respects the digitsAfterDecimal
108 * and maxNumberWidth options.
109 * @param {Number} x The number to be formatted
110 * @param {Dygraph} opts An options view
111 * @param {String} name The name of the point's data series
112 * @param {Dygraph} g The dygraph object
113 */
114 Dygraph.numberValueFormatter = function(x, opts, pt, g) {
115 var sigFigs = opts('sigFigs');
116
117 if (sigFigs !== null) {
118 // User has opted for a fixed number of significant figures.
119 return Dygraph.floatFormat(x, sigFigs);
120 }
121
122 var digits = opts('digitsAfterDecimal');
123 var maxNumberWidth = opts('maxNumberWidth');
124
125 var kmb = opts('labelsKMB');
126 var kmg2 = opts('labelsKMG2');
127
128 var label;
129
130 // switch to scientific notation if we underflow or overflow fixed display.
131 if (x !== 0.0 &&
132 (Math.abs(x) >= Math.pow(10, maxNumberWidth) ||
133 Math.abs(x) < Math.pow(10, -digits))) {
134 label = x.toExponential(digits);
135 } else {
136 label = '' + Dygraph.round_(x, digits);
137 }
138
139 if (kmb || kmg2) {
140 var k;
141 var k_labels = [];
142 var m_labels = [];
143 if (kmb) {
144 k = 1000;
145 k_labels = Dygraph.KMB_LABELS;
146 }
147 if (kmg2) {
148 if (kmb) Dygraph.warn("Setting both labelsKMB and labelsKMG2. Pick one!");
149 k = 1024;
150 k_labels = Dygraph.KMG2_BIG_LABELS;
151 m_labels = Dygraph.KMG2_SMALL_LABELS;
152 }
153
154 var absx = Math.abs(x);
155 var n = Dygraph.pow(k, k_labels.length);
156 for (var j = k_labels.length - 1; j >= 0; j--, n /= k) {
157 if (absx >= n) {
158 label = Dygraph.round_(x / n, digits) + k_labels[j];
159 break;
160 }
161 }
162 if (kmg2) {
163 // TODO(danvk): clean up this logic. Why so different than kmb?
164 var x_parts = String(x.toExponential()).split('e-');
165 if (x_parts.length === 2 && x_parts[1] >= 3 && x_parts[1] <= 24) {
166 if (x_parts[1] % 3 > 0) {
167 label = Dygraph.round_(x_parts[0] /
168 Dygraph.pow(10, (x_parts[1] % 3)),
169 digits);
170 } else {
171 label = Number(x_parts[0]).toFixed(2);
172 }
173 label += m_labels[Math.floor(x_parts[1] / 3) - 1];
174 }
175 }
176 }
177
178 return label;
179 };
180
181 /**
182 * variant for use as an axisLabelFormatter.
183 * @private
184 */
185 Dygraph.numberAxisLabelFormatter = function(x, granularity, opts, g) {
186 return Dygraph.numberValueFormatter(x, opts, g);
187 };
188
189 /**
190 * Convert a JS date (millis since epoch) to YYYY/MM/DD
191 * @param {Number} date The JavaScript date (ms since epoch)
192 * @return {String} A date of the form "YYYY/MM/DD"
193 * @private
194 */
195 Dygraph.dateString_ = function(date) {
196 var zeropad = Dygraph.zeropad;
197 var d = new Date(date);
198
199 // Get the year:
200 var year = "" + d.getFullYear();
201 // Get a 0 padded month string
202 var month = zeropad(d.getMonth() + 1); //months are 0-offset, sigh
203 // Get a 0 padded day string
204 var day = zeropad(d.getDate());
205
206 var ret = "";
207 var frac = d.getHours() * 3600 + d.getMinutes() * 60 + d.getSeconds();
208 if (frac) ret = " " + Dygraph.hmsString_(date);
209
210 return year + "/" + month + "/" + day + ret;
211 };
212
213 /**
214 * Convert a JS date to a string appropriate to display on an axis that
215 * is displaying values at the stated granularity.
216 * @param {Date} date The date to format
217 * @param {Number} granularity One of the Dygraph granularity constants
218 * @return {String} The formatted date
219 * @private
220 */
221 Dygraph.dateAxisFormatter = function(date, granularity) {
222 if (granularity >= Dygraph.DECADAL) {
223 return date.strftime('%Y');
224 } else if (granularity >= Dygraph.MONTHLY) {
225 return date.strftime('%b %y');
226 } else {
227 var frac = date.getHours() * 3600 + date.getMinutes() * 60 + date.getSeconds() + date.getMilliseconds();
228 if (frac === 0 || granularity >= Dygraph.DAILY) {
229 return new Date(date.getTime() + 3600*1000).strftime('%d%b');
230 } else {
231 return Dygraph.hmsString_(date.getTime());
232 }
233 }
234 };
235
236 /**
237 * Standard plotters. These may be used by clients.
238 * Available plotters are:
239 * - Dygraph.Plotters.linePlotter: draws central lines (most common)
240 * - Dygraph.Plotters.errorPlotter: draws error bars
241 * - Dygraph.Plotters.fillPlotter: draws fills under lines (used with fillGraph)
242 *
243 * By default, the plotter is [fillPlotter, errorPlotter, linePlotter].
244 * This causes all the lines to be drawn over all the fills/error bars.
245 */
246 Dygraph.Plotters = DygraphCanvasRenderer._Plotters;
247
248
249 // Default attribute values.
250 Dygraph.DEFAULT_ATTRS = {
251 highlightCircleSize: 3,
252 highlightSeriesOpts: null,
253 highlightSeriesBackgroundAlpha: 0.5,
254
255 labelsDivWidth: 250,
256 labelsDivStyles: {
257 // TODO(danvk): move defaults from createStatusMessage_ here.
258 },
259 labelsSeparateLines: false,
260 labelsShowZeroValues: true,
261 labelsKMB: false,
262 labelsKMG2: false,
263 showLabelsOnHighlight: true,
264
265 digitsAfterDecimal: 2,
266 maxNumberWidth: 6,
267 sigFigs: null,
268
269 strokeWidth: 1.0,
270 strokeBorderWidth: 0,
271 strokeBorderColor: "white",
272
273 axisTickSize: 3,
274 axisLabelFontSize: 14,
275 xAxisLabelWidth: 50,
276 yAxisLabelWidth: 50,
277 rightGap: 5,
278
279 showRoller: false,
280 xValueParser: Dygraph.dateParser,
281
282 delimiter: ',',
283
284 sigma: 2.0,
285 errorBars: false,
286 fractions: false,
287 wilsonInterval: true, // only relevant if fractions is true
288 customBars: false,
289 fillGraph: false,
290 fillAlpha: 0.15,
291 connectSeparatedPoints: false,
292
293 stackedGraph: false,
294 stackedGraphNaNFill: 'all',
295 hideOverlayOnMouseOut: true,
296
297 // TODO(danvk): support 'onmouseover' and 'never', and remove synonyms.
298 legend: 'onmouseover', // the only relevant value at the moment is 'always'.
299
300 stepPlot: false,
301 avoidMinZero: false,
302 xRangePad: 0,
303 yRangePad: null,
304 drawAxesAtZero: false,
305
306 // Sizes of the various chart labels.
307 titleHeight: 28,
308 xLabelHeight: 18,
309 yLabelWidth: 18,
310
311 drawXAxis: true,
312 drawYAxis: true,
313 axisLineColor: "black",
314 axisLineWidth: 0.3,
315 gridLineWidth: 0.3,
316 axisLabelColor: "black",
317 axisLabelFont: "Arial", // TODO(danvk): is this implemented?
318 axisLabelWidth: 50,
319 drawYGrid: true,
320 drawXGrid: true,
321 gridLineColor: "rgb(128,128,128)",
322
323 interactionModel: null, // will be set to Dygraph.Interaction.defaultModel
324 animatedZooms: false, // (for now)
325
326 // Range selector options
327 showRangeSelector: false,
328 rangeSelectorHeight: 40,
329 rangeSelectorPlotStrokeColor: "#808FAB",
330 rangeSelectorPlotFillColor: "#A7B1C4",
331
332 // The ordering here ensures that central lines always appear above any
333 // fill bars/error bars.
334 plotter: [
335 Dygraph.Plotters.fillPlotter,
336 Dygraph.Plotters.errorPlotter,
337 Dygraph.Plotters.linePlotter
338 ],
339
340 plugins: [ ],
341
342 // per-axis options
343 axes: {
344 x: {
345 pixelsPerLabel: 60,
346 axisLabelFormatter: Dygraph.dateAxisFormatter,
347 valueFormatter: Dygraph.dateString_,
348 drawGrid: true,
349 independentTicks: true,
350 ticker: null // will be set in dygraph-tickers.js
351 },
352 y: {
353 pixelsPerLabel: 30,
354 valueFormatter: Dygraph.numberValueFormatter,
355 axisLabelFormatter: Dygraph.numberAxisLabelFormatter,
356 drawGrid: true,
357 independentTicks: true,
358 ticker: null // will be set in dygraph-tickers.js
359 },
360 y2: {
361 pixelsPerLabel: 30,
362 valueFormatter: Dygraph.numberValueFormatter,
363 axisLabelFormatter: Dygraph.numberAxisLabelFormatter,
364 drawGrid: false,
365 independentTicks: false,
366 ticker: null // will be set in dygraph-tickers.js
367 }
368 }
369 };
370
371 // Directions for panning and zooming. Use bit operations when combined
372 // values are possible.
373 Dygraph.HORIZONTAL = 1;
374 Dygraph.VERTICAL = 2;
375
376 // Installed plugins, in order of precedence (most-general to most-specific).
377 // Plugins are installed after they are defined, in plugins/install.js.
378 Dygraph.PLUGINS = [
379 ];
380
381 // Used for initializing annotation CSS rules only once.
382 Dygraph.addedAnnotationCSS = false;
383
384 Dygraph.prototype.__old_init__ = function(div, file, labels, attrs) {
385 // Labels is no longer a constructor parameter, since it's typically set
386 // directly from the data source. It also conains a name for the x-axis,
387 // which the previous constructor form did not.
388 if (labels !== null) {
389 var new_labels = ["Date"];
390 for (var i = 0; i < labels.length; i++) new_labels.push(labels[i]);
391 Dygraph.update(attrs, { 'labels': new_labels });
392 }
393 this.__init__(div, file, attrs);
394 };
395
396 /**
397 * Initializes the Dygraph. This creates a new DIV and constructs the PlotKit
398 * and context &lt;canvas&gt; inside of it. See the constructor for details.
399 * on the parameters.
400 * @param {Element} div the Element to render the graph into.
401 * @param {String | Function} file Source data
402 * @param {Object} attrs Miscellaneous other options
403 * @private
404 */
405 Dygraph.prototype.__init__ = function(div, file, attrs) {
406 // Hack for IE: if we're using excanvas and the document hasn't finished
407 // loading yet (and hence may not have initialized whatever it needs to
408 // initialize), then keep calling this routine periodically until it has.
409 if (/MSIE/.test(navigator.userAgent) && !window.opera &&
410 typeof(G_vmlCanvasManager) != 'undefined' &&
411 document.readyState != 'complete') {
412 var self = this;
413 setTimeout(function() { self.__init__(div, file, attrs); }, 100);
414 return;
415 }
416
417 // Support two-argument constructor
418 if (attrs === null || attrs === undefined) { attrs = {}; }
419
420 attrs = Dygraph.mapLegacyOptions_(attrs);
421
422 if (typeof(div) == 'string') {
423 div = document.getElementById(div);
424 }
425
426 if (!div) {
427 Dygraph.error("Constructing dygraph with a non-existent div!");
428 return;
429 }
430
431 this.isUsingExcanvas_ = typeof(G_vmlCanvasManager) != 'undefined';
432
433 // Copy the important bits into the object
434 // TODO(danvk): most of these should just stay in the attrs_ dictionary.
435 this.maindiv_ = div;
436 this.file_ = file;
437 this.rollPeriod_ = attrs.rollPeriod || Dygraph.DEFAULT_ROLL_PERIOD;
438 this.previousVerticalX_ = -1;
439 this.fractions_ = attrs.fractions || false;
440 this.dateWindow_ = attrs.dateWindow || null;
441
442 this.is_initial_draw_ = true;
443 this.annotations_ = [];
444
445 // Zoomed indicators - These indicate when the graph has been zoomed and on what axis.
446 this.zoomed_x_ = false;
447 this.zoomed_y_ = false;
448
449 // Clear the div. This ensure that, if multiple dygraphs are passed the same
450 // div, then only one will be drawn.
451 div.innerHTML = "";
452
453 // For historical reasons, the 'width' and 'height' options trump all CSS
454 // rules _except_ for an explicit 'width' or 'height' on the div.
455 // As an added convenience, if the div has zero height (like <div></div> does
456 // without any styles), then we use a default height/width.
457 if (div.style.width === '' && attrs.width) {
458 div.style.width = attrs.width + "px";
459 }
460 if (div.style.height === '' && attrs.height) {
461 div.style.height = attrs.height + "px";
462 }
463 if (div.style.height === '' && div.clientHeight === 0) {
464 div.style.height = Dygraph.DEFAULT_HEIGHT + "px";
465 if (div.style.width === '') {
466 div.style.width = Dygraph.DEFAULT_WIDTH + "px";
467 }
468 }
469 // These will be zero if the dygraph's div is hidden. In that case,
470 // use the user-specified attributes if present. If not, use zero
471 // and assume the user will call resize to fix things later.
472 this.width_ = div.clientWidth || attrs.width || 0;
473 this.height_ = div.clientHeight || attrs.height || 0;
474
475 // TODO(danvk): set fillGraph to be part of attrs_ here, not user_attrs_.
476 if (attrs.stackedGraph) {
477 attrs.fillGraph = true;
478 // TODO(nikhilk): Add any other stackedGraph checks here.
479 }
480
481 // DEPRECATION WARNING: All option processing should be moved from
482 // attrs_ and user_attrs_ to options_, which holds all this information.
483 //
484 // Dygraphs has many options, some of which interact with one another.
485 // To keep track of everything, we maintain two sets of options:
486 //
487 // this.user_attrs_ only options explicitly set by the user.
488 // this.attrs_ defaults, options derived from user_attrs_, data.
489 //
490 // Options are then accessed this.attr_('attr'), which first looks at
491 // user_attrs_ and then computed attrs_. This way Dygraphs can set intelligent
492 // defaults without overriding behavior that the user specifically asks for.
493 this.user_attrs_ = {};
494 Dygraph.update(this.user_attrs_, attrs);
495
496 // This sequence ensures that Dygraph.DEFAULT_ATTRS is never modified.
497 this.attrs_ = {};
498 Dygraph.updateDeep(this.attrs_, Dygraph.DEFAULT_ATTRS);
499
500 this.boundaryIds_ = [];
501 this.setIndexByName_ = {};
502 this.datasetIndex_ = [];
503
504 this.registeredEvents_ = [];
505 this.eventListeners_ = {};
506
507 this.attributes_ = new DygraphOptions(this);
508
509 // Create the containing DIV and other interactive elements
510 this.createInterface_();
511
512 // Activate plugins.
513 this.plugins_ = [];
514 var plugins = Dygraph.PLUGINS.concat(this.getOption('plugins'));
515 for (var i = 0; i < plugins.length; i++) {
516 var Plugin = plugins[i];
517 var pluginInstance = new Plugin();
518 var pluginDict = {
519 plugin: pluginInstance,
520 events: {},
521 options: {},
522 pluginOptions: {}
523 };
524
525 var handlers = pluginInstance.activate(this);
526 for (var eventName in handlers) {
527 // TODO(danvk): validate eventName.
528 pluginDict.events[eventName] = handlers[eventName];
529 }
530
531 this.plugins_.push(pluginDict);
532 }
533
534 // At this point, plugins can no longer register event handlers.
535 // Construct a map from event -> ordered list of [callback, plugin].
536 for (var i = 0; i < this.plugins_.length; i++) {
537 var plugin_dict = this.plugins_[i];
538 for (var eventName in plugin_dict.events) {
539 if (!plugin_dict.events.hasOwnProperty(eventName)) continue;
540 var callback = plugin_dict.events[eventName];
541
542 var pair = [plugin_dict.plugin, callback];
543 if (!(eventName in this.eventListeners_)) {
544 this.eventListeners_[eventName] = [pair];
545 } else {
546 this.eventListeners_[eventName].push(pair);
547 }
548 }
549 }
550
551 this.createDragInterface_();
552
553 this.start_();
554 };
555
556 /**
557 * Triggers a cascade of events to the various plugins which are interested in them.
558 * Returns true if the "default behavior" should be performed, i.e. if none of
559 * the event listeners called event.preventDefault().
560 * @private
561 */
562 Dygraph.prototype.cascadeEvents_ = function(name, extra_props) {
563 if (!(name in this.eventListeners_)) return true;
564
565 // QUESTION: can we use objects & prototypes to speed this up?
566 var e = {
567 dygraph: this,
568 cancelable: false,
569 defaultPrevented: false,
570 preventDefault: function() {
571 if (!e.cancelable) throw "Cannot call preventDefault on non-cancelable event.";
572 e.defaultPrevented = true;
573 },
574 propagationStopped: false,
575 stopPropagation: function() {
576 e.propagationStopped = true;
577 }
578 };
579 Dygraph.update(e, extra_props);
580
581 var callback_plugin_pairs = this.eventListeners_[name];
582 if (callback_plugin_pairs) {
583 for (var i = callback_plugin_pairs.length - 1; i >= 0; i--) {
584 var plugin = callback_plugin_pairs[i][0];
585 var callback = callback_plugin_pairs[i][1];
586 callback.call(plugin, e);
587 if (e.propagationStopped) break;
588 }
589 }
590 return e.defaultPrevented;
591 };
592
593 /**
594 * Returns the zoomed status of the chart for one or both axes.
595 *
596 * Axis is an optional parameter. Can be set to 'x' or 'y'.
597 *
598 * The zoomed status for an axis is set whenever a user zooms using the mouse
599 * or when the dateWindow or valueRange are updated (unless the
600 * isZoomedIgnoreProgrammaticZoom option is also specified).
601 */
602 Dygraph.prototype.isZoomed = function(axis) {
603 if (axis === null || axis === undefined) {
604 return this.zoomed_x_ || this.zoomed_y_;
605 }
606 if (axis === 'x') return this.zoomed_x_;
607 if (axis === 'y') return this.zoomed_y_;
608 throw "axis parameter is [" + axis + "] must be null, 'x' or 'y'.";
609 };
610
611 /**
612 * Returns information about the Dygraph object, including its containing ID.
613 */
614 Dygraph.prototype.toString = function() {
615 var maindiv = this.maindiv_;
616 var id = (maindiv && maindiv.id) ? maindiv.id : maindiv;
617 return "[Dygraph " + id + "]";
618 };
619
620 /**
621 * @private
622 * Returns the value of an option. This may be set by the user (either in the
623 * constructor or by calling updateOptions) or by dygraphs, and may be set to a
624 * per-series value.
625 * @param { String } name The name of the option, e.g. 'rollPeriod'.
626 * @param { String } [seriesName] The name of the series to which the option
627 * will be applied. If no per-series value of this option is available, then
628 * the global value is returned. This is optional.
629 * @return { ... } The value of the option.
630 */
631 Dygraph.prototype.attr_ = function(name, seriesName) {
632 // <REMOVE_FOR_COMBINED>
633 if (typeof(Dygraph.OPTIONS_REFERENCE) === 'undefined') {
634 this.error('Must include options reference JS for testing');
635 } else if (!Dygraph.OPTIONS_REFERENCE.hasOwnProperty(name)) {
636 this.error('Dygraphs is using property ' + name + ', which has no entry ' +
637 'in the Dygraphs.OPTIONS_REFERENCE listing.');
638 // Only log this error once.
639 Dygraph.OPTIONS_REFERENCE[name] = true;
640 }
641 // </REMOVE_FOR_COMBINED>
642 return seriesName ? this.attributes_.getForSeries(name, seriesName) : this.attributes_.get(name);
643 };
644
645 /**
646 * Returns the current value for an option, as set in the constructor or via
647 * updateOptions. You may pass in an (optional) series name to get per-series
648 * values for the option.
649 *
650 * All values returned by this method should be considered immutable. If you
651 * modify them, there is no guarantee that the changes will be honored or that
652 * dygraphs will remain in a consistent state. If you want to modify an option,
653 * use updateOptions() instead.
654 *
655 * @param { String } name The name of the option (e.g. 'strokeWidth')
656 * @param { String } [opt_seriesName] Series name to get per-series values.
657 * @return { ... } The value of the option.
658 */
659 Dygraph.prototype.getOption = function(name, opt_seriesName) {
660 return this.attr_(name, opt_seriesName);
661 };
662
663 Dygraph.prototype.getOptionForAxis = function(name, axis) {
664 return this.attributes_.getForAxis(name, axis);
665 };
666
667 /**
668 * @private
669 * @param String} axis The name of the axis (i.e. 'x', 'y' or 'y2')
670 * @return { ... } A function mapping string -> option value
671 */
672 Dygraph.prototype.optionsViewForAxis_ = function(axis) {
673 var self = this;
674 return function(opt) {
675 var axis_opts = self.user_attrs_.axes;
676 if (axis_opts && axis_opts[axis] && axis_opts[axis].hasOwnProperty(opt)) {
677 return axis_opts[axis][opt];
678 }
679 // user-specified attributes always trump defaults, even if they're less
680 // specific.
681 if (typeof(self.user_attrs_[opt]) != 'undefined') {
682 return self.user_attrs_[opt];
683 }
684
685 axis_opts = self.attrs_.axes;
686 if (axis_opts && axis_opts[axis] && axis_opts[axis].hasOwnProperty(opt)) {
687 return axis_opts[axis][opt];
688 }
689 // check old-style axis options
690 // TODO(danvk): add a deprecation warning if either of these match.
691 if (axis == 'y' && self.axes_[0].hasOwnProperty(opt)) {
692 return self.axes_[0][opt];
693 } else if (axis == 'y2' && self.axes_[1].hasOwnProperty(opt)) {
694 return self.axes_[1][opt];
695 }
696 return self.attr_(opt);
697 };
698 };
699
700 /**
701 * Returns the current rolling period, as set by the user or an option.
702 * @return {Number} The number of points in the rolling window
703 */
704 Dygraph.prototype.rollPeriod = function() {
705 return this.rollPeriod_;
706 };
707
708 /**
709 * Returns the currently-visible x-range. This can be affected by zooming,
710 * panning or a call to updateOptions.
711 * Returns a two-element array: [left, right].
712 * If the Dygraph has dates on the x-axis, these will be millis since epoch.
713 */
714 Dygraph.prototype.xAxisRange = function() {
715 return this.dateWindow_ ? this.dateWindow_ : this.xAxisExtremes();
716 };
717
718 /**
719 * Returns the lower- and upper-bound x-axis values of the
720 * data set.
721 */
722 Dygraph.prototype.xAxisExtremes = function() {
723 var pad = this.attr_('xRangePad') / this.plotter_.area.w;
724 if (this.numRows() === 0) {
725 return [0 - pad, 1 + pad];
726 }
727 var left = this.rawData_[0][0];
728 var right = this.rawData_[this.rawData_.length - 1][0];
729 if (pad) {
730 // Must keep this in sync with dygraph-layout _evaluateLimits()
731 var range = right - left;
732 left -= range * pad;
733 right += range * pad;
734 }
735 return [left, right];
736 };
737
738 /**
739 * Returns the currently-visible y-range for an axis. This can be affected by
740 * zooming, panning or a call to updateOptions. Axis indices are zero-based. If
741 * called with no arguments, returns the range of the first axis.
742 * Returns a two-element array: [bottom, top].
743 */
744 Dygraph.prototype.yAxisRange = function(idx) {
745 if (typeof(idx) == "undefined") idx = 0;
746 if (idx < 0 || idx >= this.axes_.length) {
747 return null;
748 }
749 var axis = this.axes_[idx];
750 return [ axis.computedValueRange[0], axis.computedValueRange[1] ];
751 };
752
753 /**
754 * Returns the currently-visible y-ranges for each axis. This can be affected by
755 * zooming, panning, calls to updateOptions, etc.
756 * Returns an array of [bottom, top] pairs, one for each y-axis.
757 */
758 Dygraph.prototype.yAxisRanges = function() {
759 var ret = [];
760 for (var i = 0; i < this.axes_.length; i++) {
761 ret.push(this.yAxisRange(i));
762 }
763 return ret;
764 };
765
766 // TODO(danvk): use these functions throughout dygraphs.
767 /**
768 * Convert from data coordinates to canvas/div X/Y coordinates.
769 * If specified, do this conversion for the coordinate system of a particular
770 * axis. Uses the first axis by default.
771 * Returns a two-element array: [X, Y]
772 *
773 * Note: use toDomXCoord instead of toDomCoords(x, null) and use toDomYCoord
774 * instead of toDomCoords(null, y, axis).
775 */
776 Dygraph.prototype.toDomCoords = function(x, y, axis) {
777 return [ this.toDomXCoord(x), this.toDomYCoord(y, axis) ];
778 };
779
780 /**
781 * Convert from data x coordinates to canvas/div X coordinate.
782 * If specified, do this conversion for the coordinate system of a particular
783 * axis.
784 * Returns a single value or null if x is null.
785 */
786 Dygraph.prototype.toDomXCoord = function(x) {
787 if (x === null) {
788 return null;
789 }
790
791 var area = this.plotter_.area;
792 var xRange = this.xAxisRange();
793 return area.x + (x - xRange[0]) / (xRange[1] - xRange[0]) * area.w;
794 };
795
796 /**
797 * Convert from data x coordinates to canvas/div Y coordinate and optional
798 * axis. Uses the first axis by default.
799 *
800 * returns a single value or null if y is null.
801 */
802 Dygraph.prototype.toDomYCoord = function(y, axis) {
803 var pct = this.toPercentYCoord(y, axis);
804
805 if (pct === null) {
806 return null;
807 }
808 var area = this.plotter_.area;
809 return area.y + pct * area.h;
810 };
811
812 /**
813 * Convert from canvas/div coords to data coordinates.
814 * If specified, do this conversion for the coordinate system of a particular
815 * axis. Uses the first axis by default.
816 * Returns a two-element array: [X, Y].
817 *
818 * Note: use toDataXCoord instead of toDataCoords(x, null) and use toDataYCoord
819 * instead of toDataCoords(null, y, axis).
820 */
821 Dygraph.prototype.toDataCoords = function(x, y, axis) {
822 return [ this.toDataXCoord(x), this.toDataYCoord(y, axis) ];
823 };
824
825 /**
826 * Convert from canvas/div x coordinate to data coordinate.
827 *
828 * If x is null, this returns null.
829 */
830 Dygraph.prototype.toDataXCoord = function(x) {
831 if (x === null) {
832 return null;
833 }
834
835 var area = this.plotter_.area;
836 var xRange = this.xAxisRange();
837 return xRange[0] + (x - area.x) / area.w * (xRange[1] - xRange[0]);
838 };
839
840 /**
841 * Convert from canvas/div y coord to value.
842 *
843 * If y is null, this returns null.
844 * if axis is null, this uses the first axis.
845 */
846 Dygraph.prototype.toDataYCoord = function(y, axis) {
847 if (y === null) {
848 return null;
849 }
850
851 var area = this.plotter_.area;
852 var yRange = this.yAxisRange(axis);
853
854 if (typeof(axis) == "undefined") axis = 0;
855 if (!this.axes_[axis].logscale) {
856 return yRange[0] + (area.y + area.h - y) / area.h * (yRange[1] - yRange[0]);
857 } else {
858 // Computing the inverse of toDomCoord.
859 var pct = (y - area.y) / area.h;
860
861 // Computing the inverse of toPercentYCoord. The function was arrived at with
862 // the following steps:
863 //
864 // Original calcuation:
865 // pct = (logr1 - Dygraph.log10(y)) / (logr1 - Dygraph.log10(yRange[0]));
866 //
867 // Move denominator to both sides:
868 // pct * (logr1 - Dygraph.log10(yRange[0])) = logr1 - Dygraph.log10(y);
869 //
870 // subtract logr1, and take the negative value.
871 // logr1 - (pct * (logr1 - Dygraph.log10(yRange[0]))) = Dygraph.log10(y);
872 //
873 // Swap both sides of the equation, and we can compute the log of the
874 // return value. Which means we just need to use that as the exponent in
875 // e^exponent.
876 // Dygraph.log10(y) = logr1 - (pct * (logr1 - Dygraph.log10(yRange[0])));
877
878 var logr1 = Dygraph.log10(yRange[1]);
879 var exponent = logr1 - (pct * (logr1 - Dygraph.log10(yRange[0])));
880 var value = Math.pow(Dygraph.LOG_SCALE, exponent);
881 return value;
882 }
883 };
884
885 /**
886 * Converts a y for an axis to a percentage from the top to the
887 * bottom of the drawing area.
888 *
889 * If the coordinate represents a value visible on the canvas, then
890 * the value will be between 0 and 1, where 0 is the top of the canvas.
891 * However, this method will return values outside the range, as
892 * values can fall outside the canvas.
893 *
894 * If y is null, this returns null.
895 * if axis is null, this uses the first axis.
896 *
897 * @param { Number } y The data y-coordinate.
898 * @param { Number } [axis] The axis number on which the data coordinate lives.
899 * @return { Number } A fraction in [0, 1] where 0 = the top edge.
900 */
901 Dygraph.prototype.toPercentYCoord = function(y, axis) {
902 if (y === null) {
903 return null;
904 }
905 if (typeof(axis) == "undefined") axis = 0;
906
907 var yRange = this.yAxisRange(axis);
908
909 var pct;
910 var logscale = this.attributes_.getForAxis("logscale", axis);
911 if (!logscale) {
912 // yRange[1] - y is unit distance from the bottom.
913 // yRange[1] - yRange[0] is the scale of the range.
914 // (yRange[1] - y) / (yRange[1] - yRange[0]) is the % from the bottom.
915 pct = (yRange[1] - y) / (yRange[1] - yRange[0]);
916 } else {
917 var logr1 = Dygraph.log10(yRange[1]);
918 pct = (logr1 - Dygraph.log10(y)) / (logr1 - Dygraph.log10(yRange[0]));
919 }
920 return pct;
921 };
922
923 /**
924 * Converts an x value to a percentage from the left to the right of
925 * the drawing area.
926 *
927 * If the coordinate represents a value visible on the canvas, then
928 * the value will be between 0 and 1, where 0 is the left of the canvas.
929 * However, this method will return values outside the range, as
930 * values can fall outside the canvas.
931 *
932 * If x is null, this returns null.
933 * @param { Number } x The data x-coordinate.
934 * @return { Number } A fraction in [0, 1] where 0 = the left edge.
935 */
936 Dygraph.prototype.toPercentXCoord = function(x) {
937 if (x === null) {
938 return null;
939 }
940
941 var xRange = this.xAxisRange();
942 return (x - xRange[0]) / (xRange[1] - xRange[0]);
943 };
944
945 /**
946 * Returns the number of columns (including the independent variable).
947 * @return { Integer } The number of columns.
948 */
949 Dygraph.prototype.numColumns = function() {
950 if (!this.rawData_) return 0;
951 return this.rawData_[0] ? this.rawData_[0].length : this.attr_("labels").length;
952 };
953
954 /**
955 * Returns the number of rows (excluding any header/label row).
956 * @return { Integer } The number of rows, less any header.
957 */
958 Dygraph.prototype.numRows = function() {
959 if (!this.rawData_) return 0;
960 return this.rawData_.length;
961 };
962
963 /**
964 * Returns the value in the given row and column. If the row and column exceed
965 * the bounds on the data, returns null. Also returns null if the value is
966 * missing.
967 * @param { Number} row The row number of the data (0-based). Row 0 is the
968 * first row of data, not a header row.
969 * @param { Number} col The column number of the data (0-based)
970 * @return { Number } The value in the specified cell or null if the row/col
971 * were out of range.
972 */
973 Dygraph.prototype.getValue = function(row, col) {
974 if (row < 0 || row > this.rawData_.length) return null;
975 if (col < 0 || col > this.rawData_[row].length) return null;
976
977 return this.rawData_[row][col];
978 };
979
980 /**
981 * Generates interface elements for the Dygraph: a containing div, a div to
982 * display the current point, and a textbox to adjust the rolling average
983 * period. Also creates the Renderer/Layout elements.
984 * @private
985 */
986 Dygraph.prototype.createInterface_ = function() {
987 // Create the all-enclosing graph div
988 var enclosing = this.maindiv_;
989
990 this.graphDiv = document.createElement("div");
991
992 // TODO(danvk): any other styles that are useful to set here?
993 this.graphDiv.style.textAlign = 'left'; // This is a CSS "reset"
994 enclosing.appendChild(this.graphDiv);
995
996 // Create the canvas for interactive parts of the chart.
997 this.canvas_ = Dygraph.createCanvas();
998 this.canvas_.style.position = "absolute";
999
1000 // ... and for static parts of the chart.
1001 this.hidden_ = this.createPlotKitCanvas_(this.canvas_);
1002
1003 this.resizeElements_();
1004
1005 this.canvas_ctx_ = Dygraph.getContext(this.canvas_);
1006 this.hidden_ctx_ = Dygraph.getContext(this.hidden_);
1007
1008 // The interactive parts of the graph are drawn on top of the chart.
1009 this.graphDiv.appendChild(this.hidden_);
1010 this.graphDiv.appendChild(this.canvas_);
1011 this.mouseEventElement_ = this.createMouseEventElement_();
1012
1013 // Create the grapher
1014 this.layout_ = new DygraphLayout(this);
1015
1016 var dygraph = this;
1017
1018 this.mouseMoveHandler_ = function(e) {
1019 dygraph.mouseMove_(e);
1020 };
1021
1022 this.mouseOutHandler_ = function(e) {
1023 // The mouse has left the chart if:
1024 // 1. e.target is inside the chart
1025 // 2. e.relatedTarget is outside the chart
1026 var target = e.target || e.fromElement;
1027 var relatedTarget = e.relatedTarget || e.toElement;
1028 if (Dygraph.isNodeContainedBy(target, dygraph.graphDiv) &&
1029 !Dygraph.isNodeContainedBy(relatedTarget, dygraph.graphDiv)) {
1030 dygraph.mouseOut_(e);
1031 }
1032 };
1033
1034 this.addAndTrackEvent(window, 'mouseout', this.mouseOutHandler_);
1035 this.addAndTrackEvent(this.mouseEventElement_, 'mousemove', this.mouseMoveHandler_);
1036
1037 // Don't recreate and register the resize handler on subsequent calls.
1038 // This happens when the graph is resized.
1039 if (!this.resizeHandler_) {
1040 this.resizeHandler_ = function(e) {
1041 dygraph.resize();
1042 };
1043
1044 // Update when the window is resized.
1045 // TODO(danvk): drop frames depending on complexity of the chart.
1046 this.addAndTrackEvent(window, 'resize', this.resizeHandler_);
1047 }
1048 };
1049
1050 Dygraph.prototype.resizeElements_ = function() {
1051 this.graphDiv.style.width = this.width_ + "px";
1052 this.graphDiv.style.height = this.height_ + "px";
1053 this.canvas_.width = this.width_;
1054 this.canvas_.height = this.height_;
1055 this.canvas_.style.width = this.width_ + "px"; // for IE
1056 this.canvas_.style.height = this.height_ + "px"; // for IE
1057 this.hidden_.width = this.width_;
1058 this.hidden_.height = this.height_;
1059 this.hidden_.style.width = this.width_ + "px"; // for IE
1060 this.hidden_.style.height = this.height_ + "px"; // for IE
1061 };
1062
1063 /**
1064 * Detach DOM elements in the dygraph and null out all data references.
1065 * Calling this when you're done with a dygraph can dramatically reduce memory
1066 * usage. See, e.g., the tests/perf.html example.
1067 */
1068 Dygraph.prototype.destroy = function() {
1069 this.canvas_ctx_.restore();
1070 this.hidden_ctx_.restore();
1071
1072 var removeRecursive = function(node) {
1073 while (node.hasChildNodes()) {
1074 removeRecursive(node.firstChild);
1075 node.removeChild(node.firstChild);
1076 }
1077 };
1078
1079 this.removeTrackedEvents_();
1080
1081 // remove mouse event handlers (This may not be necessary anymore)
1082 Dygraph.removeEvent(window, 'mouseout', this.mouseOutHandler_);
1083 Dygraph.removeEvent(this.mouseEventElement_, 'mousemove', this.mouseMoveHandler_);
1084
1085 // remove window handlers
1086 Dygraph.removeEvent(window,'resize',this.resizeHandler_);
1087 this.resizeHandler_ = null;
1088
1089 removeRecursive(this.maindiv_);
1090
1091 var nullOut = function(obj) {
1092 for (var n in obj) {
1093 if (typeof(obj[n]) === 'object') {
1094 obj[n] = null;
1095 }
1096 }
1097 };
1098 // These may not all be necessary, but it can't hurt...
1099 nullOut(this.layout_);
1100 nullOut(this.plotter_);
1101 nullOut(this);
1102 };
1103
1104 /**
1105 * Creates the canvas on which the chart will be drawn. Only the Renderer ever
1106 * draws on this particular canvas. All Dygraph work (i.e. drawing hover dots
1107 * or the zoom rectangles) is done on this.canvas_.
1108 * @param {Object} canvas The Dygraph canvas over which to overlay the plot
1109 * @return {Object} The newly-created canvas
1110 * @private
1111 */
1112 Dygraph.prototype.createPlotKitCanvas_ = function(canvas) {
1113 var h = Dygraph.createCanvas();
1114 h.style.position = "absolute";
1115 // TODO(danvk): h should be offset from canvas. canvas needs to include
1116 // some extra area to make it easier to zoom in on the far left and far
1117 // right. h needs to be precisely the plot area, so that clipping occurs.
1118 h.style.top = canvas.style.top;
1119 h.style.left = canvas.style.left;
1120 h.width = this.width_;
1121 h.height = this.height_;
1122 h.style.width = this.width_ + "px"; // for IE
1123 h.style.height = this.height_ + "px"; // for IE
1124 return h;
1125 };
1126
1127 /**
1128 * Creates an overlay element used to handle mouse events.
1129 * @return {Object} The mouse event element.
1130 * @private
1131 */
1132 Dygraph.prototype.createMouseEventElement_ = function() {
1133 if (this.isUsingExcanvas_) {
1134 var elem = document.createElement("div");
1135 elem.style.position = 'absolute';
1136 elem.style.backgroundColor = 'white';
1137 elem.style.filter = 'alpha(opacity=0)';
1138 elem.style.width = this.width_ + "px";
1139 elem.style.height = this.height_ + "px";
1140 this.graphDiv.appendChild(elem);
1141 return elem;
1142 } else {
1143 return this.canvas_;
1144 }
1145 };
1146
1147 /**
1148 * Generate a set of distinct colors for the data series. This is done with a
1149 * color wheel. Saturation/Value are customizable, and the hue is
1150 * equally-spaced around the color wheel. If a custom set of colors is
1151 * specified, that is used instead.
1152 * @private
1153 */
1154 Dygraph.prototype.setColors_ = function() {
1155 var labels = this.getLabels();
1156 var num = labels.length - 1;
1157 this.colors_ = [];
1158 this.colorsMap_ = {};
1159 var colors = this.attr_('colors');
1160 var i;
1161 if (!colors) {
1162 var sat = this.attr_('colorSaturation') || 1.0;
1163 var val = this.attr_('colorValue') || 0.5;
1164 var half = Math.ceil(num / 2);
1165 for (i = 1; i <= num; i++) {
1166 if (!this.visibility()[i-1]) continue;
1167 // alternate colors for high contrast.
1168 var idx = i % 2 ? Math.ceil(i / 2) : (half + i / 2);
1169 var hue = (1.0 * idx/ (1 + num));
1170 var colorStr = Dygraph.hsvToRGB(hue, sat, val);
1171 this.colors_.push(colorStr);
1172 this.colorsMap_[labels[i]] = colorStr;
1173 }
1174 } else {
1175 for (i = 0; i < num; i++) {
1176 if (!this.visibility()[i]) continue;
1177 var colorStr = colors[i % colors.length];
1178 this.colors_.push(colorStr);
1179 this.colorsMap_[labels[1 + i]] = colorStr;
1180 }
1181 }
1182 };
1183
1184 /**
1185 * Return the list of colors. This is either the list of colors passed in the
1186 * attributes or the autogenerated list of rgb(r,g,b) strings.
1187 * This does not return colors for invisible series.
1188 * @return {Array<string>} The list of colors.
1189 */
1190 Dygraph.prototype.getColors = function() {
1191 return this.colors_;
1192 };
1193
1194 /**
1195 * Returns a few attributes of a series, i.e. its color, its visibility, which
1196 * axis it's assigned to, and its column in the original data.
1197 * Returns null if the series does not exist.
1198 * Otherwise, returns an object with column, visibility, color and axis properties.
1199 * The "axis" property will be set to 1 for y1 and 2 for y2.
1200 * The "column" property can be fed back into getValue(row, column) to get
1201 * values for this series.
1202 */
1203 Dygraph.prototype.getPropertiesForSeries = function(series_name) {
1204 var idx = -1;
1205 var labels = this.getLabels();
1206 for (var i = 1; i < labels.length; i++) {
1207 if (labels[i] == series_name) {
1208 idx = i;
1209 break;
1210 }
1211 }
1212 if (idx == -1) return null;
1213
1214 return {
1215 name: series_name,
1216 column: idx,
1217 visible: this.visibility()[idx - 1],
1218 color: this.colorsMap_[series_name],
1219 axis: 1 + this.attributes_.axisForSeries(series_name)
1220 };
1221 };
1222
1223 /**
1224 * Create the text box to adjust the averaging period
1225 * @private
1226 */
1227 Dygraph.prototype.createRollInterface_ = function() {
1228 // Create a roller if one doesn't exist already.
1229 if (!this.roller_) {
1230 this.roller_ = document.createElement("input");
1231 this.roller_.type = "text";
1232 this.roller_.style.display = "none";
1233 this.graphDiv.appendChild(this.roller_);
1234 }
1235
1236 var display = this.attr_('showRoller') ? 'block' : 'none';
1237
1238 var area = this.plotter_.area;
1239 var textAttr = { "position": "absolute",
1240 "zIndex": 10,
1241 "top": (area.y + area.h - 25) + "px",
1242 "left": (area.x + 1) + "px",
1243 "display": display
1244 };
1245 this.roller_.size = "2";
1246 this.roller_.value = this.rollPeriod_;
1247 for (var name in textAttr) {
1248 if (textAttr.hasOwnProperty(name)) {
1249 this.roller_.style[name] = textAttr[name];
1250 }
1251 }
1252
1253 var dygraph = this;
1254 this.roller_.onchange = function() { dygraph.adjustRoll(dygraph.roller_.value); };
1255 };
1256
1257 /**
1258 * @private
1259 * Converts page the x-coordinate of the event to pixel x-coordinates on the
1260 * canvas (i.e. DOM Coords).
1261 */
1262 Dygraph.prototype.dragGetX_ = function(e, context) {
1263 return Dygraph.pageX(e) - context.px;
1264 };
1265
1266 /**
1267 * @private
1268 * Converts page the y-coordinate of the event to pixel y-coordinates on the
1269 * canvas (i.e. DOM Coords).
1270 */
1271 Dygraph.prototype.dragGetY_ = function(e, context) {
1272 return Dygraph.pageY(e) - context.py;
1273 };
1274
1275 /**
1276 * Set up all the mouse handlers needed to capture dragging behavior for zoom
1277 * events.
1278 * @private
1279 */
1280 Dygraph.prototype.createDragInterface_ = function() {
1281 var context = {
1282 // Tracks whether the mouse is down right now
1283 isZooming: false,
1284 isPanning: false, // is this drag part of a pan?
1285 is2DPan: false, // if so, is that pan 1- or 2-dimensional?
1286 dragStartX: null, // pixel coordinates
1287 dragStartY: null, // pixel coordinates
1288 dragEndX: null, // pixel coordinates
1289 dragEndY: null, // pixel coordinates
1290 dragDirection: null,
1291 prevEndX: null, // pixel coordinates
1292 prevEndY: null, // pixel coordinates
1293 prevDragDirection: null,
1294 cancelNextDblclick: false, // see comment in dygraph-interaction-model.js
1295
1296 // The value on the left side of the graph when a pan operation starts.
1297 initialLeftmostDate: null,
1298
1299 // The number of units each pixel spans. (This won't be valid for log
1300 // scales)
1301 xUnitsPerPixel: null,
1302
1303 // TODO(danvk): update this comment
1304 // The range in second/value units that the viewport encompasses during a
1305 // panning operation.
1306 dateRange: null,
1307
1308 // Top-left corner of the canvas, in DOM coords
1309 // TODO(konigsberg): Rename topLeftCanvasX, topLeftCanvasY.
1310 px: 0,
1311 py: 0,
1312
1313 // Values for use with panEdgeFraction, which limit how far outside the
1314 // graph's data boundaries it can be panned.
1315 boundedDates: null, // [minDate, maxDate]
1316 boundedValues: null, // [[minValue, maxValue] ...]
1317
1318 // We cover iframes during mouse interactions. See comments in
1319 // dygraph-utils.js for more info on why this is a good idea.
1320 tarp: new Dygraph.IFrameTarp(),
1321
1322 // contextB is the same thing as this context object but renamed.
1323 initializeMouseDown: function(event, g, contextB) {
1324 // prevents mouse drags from selecting page text.
1325 if (event.preventDefault) {
1326 event.preventDefault(); // Firefox, Chrome, etc.
1327 } else {
1328 event.returnValue = false; // IE
1329 event.cancelBubble = true;
1330 }
1331
1332 contextB.px = Dygraph.findPosX(g.canvas_);
1333 contextB.py = Dygraph.findPosY(g.canvas_);
1334 contextB.dragStartX = g.dragGetX_(event, contextB);
1335 contextB.dragStartY = g.dragGetY_(event, contextB);
1336 contextB.cancelNextDblclick = false;
1337 contextB.tarp.cover();
1338 }
1339 };
1340
1341 var interactionModel = this.attr_("interactionModel");
1342
1343 // Self is the graph.
1344 var self = this;
1345
1346 // Function that binds the graph and context to the handler.
1347 var bindHandler = function(handler) {
1348 return function(event) {
1349 handler(event, self, context);
1350 };
1351 };
1352
1353 for (var eventName in interactionModel) {
1354 if (!interactionModel.hasOwnProperty(eventName)) continue;
1355 this.addAndTrackEvent(this.mouseEventElement_, eventName,
1356 bindHandler(interactionModel[eventName]));
1357 }
1358
1359 // If the user releases the mouse button during a drag, but not over the
1360 // canvas, then it doesn't count as a zooming action.
1361 var mouseUpHandler = function(event) {
1362 if (context.isZooming || context.isPanning) {
1363 context.isZooming = false;
1364 context.dragStartX = null;
1365 context.dragStartY = null;
1366 }
1367
1368 if (context.isPanning) {
1369 context.isPanning = false;
1370 context.draggingDate = null;
1371 context.dateRange = null;
1372 for (var i = 0; i < self.axes_.length; i++) {
1373 delete self.axes_[i].draggingValue;
1374 delete self.axes_[i].dragValueRange;
1375 }
1376 }
1377
1378 context.tarp.uncover();
1379 };
1380
1381 this.addAndTrackEvent(document, 'mouseup', mouseUpHandler);
1382 };
1383
1384 /**
1385 * Draw a gray zoom rectangle over the desired area of the canvas. Also clears
1386 * up any previous zoom rectangles that were drawn. This could be optimized to
1387 * avoid extra redrawing, but it's tricky to avoid interactions with the status
1388 * dots.
1389 *
1390 * @param {Number} direction the direction of the zoom rectangle. Acceptable
1391 * values are Dygraph.HORIZONTAL and Dygraph.VERTICAL.
1392 * @param {Number} startX The X position where the drag started, in canvas
1393 * coordinates.
1394 * @param {Number} endX The current X position of the drag, in canvas coords.
1395 * @param {Number} startY The Y position where the drag started, in canvas
1396 * coordinates.
1397 * @param {Number} endY The current Y position of the drag, in canvas coords.
1398 * @param {Number} prevDirection the value of direction on the previous call to
1399 * this function. Used to avoid excess redrawing
1400 * @param {Number} prevEndX The value of endX on the previous call to this
1401 * function. Used to avoid excess redrawing
1402 * @param {Number} prevEndY The value of endY on the previous call to this
1403 * function. Used to avoid excess redrawing
1404 * @private
1405 */
1406 Dygraph.prototype.drawZoomRect_ = function(direction, startX, endX, startY,
1407 endY, prevDirection, prevEndX,
1408 prevEndY) {
1409 var ctx = this.canvas_ctx_;
1410
1411 // Clean up from the previous rect if necessary
1412 if (prevDirection == Dygraph.HORIZONTAL) {
1413 ctx.clearRect(Math.min(startX, prevEndX), this.layout_.getPlotArea().y,
1414 Math.abs(startX - prevEndX), this.layout_.getPlotArea().h);
1415 } else if (prevDirection == Dygraph.VERTICAL){
1416 ctx.clearRect(this.layout_.getPlotArea().x, Math.min(startY, prevEndY),
1417 this.layout_.getPlotArea().w, Math.abs(startY - prevEndY));
1418 }
1419
1420 // Draw a light-grey rectangle to show the new viewing area
1421 if (direction == Dygraph.HORIZONTAL) {
1422 if (endX && startX) {
1423 ctx.fillStyle = "rgba(128,128,128,0.33)";
1424 ctx.fillRect(Math.min(startX, endX), this.layout_.getPlotArea().y,
1425 Math.abs(endX - startX), this.layout_.getPlotArea().h);
1426 }
1427 } else if (direction == Dygraph.VERTICAL) {
1428 if (endY && startY) {
1429 ctx.fillStyle = "rgba(128,128,128,0.33)";
1430 ctx.fillRect(this.layout_.getPlotArea().x, Math.min(startY, endY),
1431 this.layout_.getPlotArea().w, Math.abs(endY - startY));
1432 }
1433 }
1434
1435 if (this.isUsingExcanvas_) {
1436 this.currentZoomRectArgs_ = [direction, startX, endX, startY, endY, 0, 0, 0];
1437 }
1438 };
1439
1440 /**
1441 * Clear the zoom rectangle (and perform no zoom).
1442 * @private
1443 */
1444 Dygraph.prototype.clearZoomRect_ = function() {
1445 this.currentZoomRectArgs_ = null;
1446 this.canvas_ctx_.clearRect(0, 0, this.canvas_.width, this.canvas_.height);
1447 };
1448
1449 /**
1450 * Zoom to something containing [lowX, highX]. These are pixel coordinates in
1451 * the canvas. The exact zoom window may be slightly larger if there are no data
1452 * points near lowX or highX. Don't confuse this function with doZoomXDates,
1453 * which accepts dates that match the raw data. This function redraws the graph.
1454 *
1455 * @param {Number} lowX The leftmost pixel value that should be visible.
1456 * @param {Number} highX The rightmost pixel value that should be visible.
1457 * @private
1458 */
1459 Dygraph.prototype.doZoomX_ = function(lowX, highX) {
1460 this.currentZoomRectArgs_ = null;
1461 // Find the earliest and latest dates contained in this canvasx range.
1462 // Convert the call to date ranges of the raw data.
1463 var minDate = this.toDataXCoord(lowX);
1464 var maxDate = this.toDataXCoord(highX);
1465 this.doZoomXDates_(minDate, maxDate);
1466 };
1467
1468 /**
1469 * Transition function to use in animations. Returns values between 0.0
1470 * (totally old values) and 1.0 (totally new values) for each frame.
1471 * @private
1472 */
1473 Dygraph.zoomAnimationFunction = function(frame, numFrames) {
1474 var k = 1.5;
1475 return (1.0 - Math.pow(k, -frame)) / (1.0 - Math.pow(k, -numFrames));
1476 };
1477
1478 /**
1479 * Zoom to something containing [minDate, maxDate] values. Don't confuse this
1480 * method with doZoomX which accepts pixel coordinates. This function redraws
1481 * the graph.
1482 *
1483 * @param {Number} minDate The minimum date that should be visible.
1484 * @param {Number} maxDate The maximum date that should be visible.
1485 * @private
1486 */
1487 Dygraph.prototype.doZoomXDates_ = function(minDate, maxDate) {
1488 // TODO(danvk): when yAxisRange is null (i.e. "fit to data", the animation
1489 // can produce strange effects. Rather than the y-axis transitioning slowly
1490 // between values, it can jerk around.)
1491 var old_window = this.xAxisRange();
1492 var new_window = [minDate, maxDate];
1493 this.zoomed_x_ = true;
1494 var that = this;
1495 this.doAnimatedZoom(old_window, new_window, null, null, function() {
1496 if (that.attr_("zoomCallback")) {
1497 that.attr_("zoomCallback")(minDate, maxDate, that.yAxisRanges());
1498 }
1499 });
1500 };
1501
1502 /**
1503 * Zoom to something containing [lowY, highY]. These are pixel coordinates in
1504 * the canvas. This function redraws the graph.
1505 *
1506 * @param {Number} lowY The topmost pixel value that should be visible.
1507 * @param {Number} highY The lowest pixel value that should be visible.
1508 * @private
1509 */
1510 Dygraph.prototype.doZoomY_ = function(lowY, highY) {
1511 this.currentZoomRectArgs_ = null;
1512 // Find the highest and lowest values in pixel range for each axis.
1513 // Note that lowY (in pixels) corresponds to the max Value (in data coords).
1514 // This is because pixels increase as you go down on the screen, whereas data
1515 // coordinates increase as you go up the screen.
1516 var oldValueRanges = this.yAxisRanges();
1517 var newValueRanges = [];
1518 for (var i = 0; i < this.axes_.length; i++) {
1519 var hi = this.toDataYCoord(lowY, i);
1520 var low = this.toDataYCoord(highY, i);
1521 newValueRanges.push([low, hi]);
1522 }
1523
1524 this.zoomed_y_ = true;
1525 var that = this;
1526 this.doAnimatedZoom(null, null, oldValueRanges, newValueRanges, function() {
1527 if (that.attr_("zoomCallback")) {
1528 var xRange = that.xAxisRange();
1529 that.attr_("zoomCallback")(xRange[0], xRange[1], that.yAxisRanges());
1530 }
1531 });
1532 };
1533
1534 /**
1535 * Reset the zoom to the original view coordinates. This is the same as
1536 * double-clicking on the graph.
1537 */
1538 Dygraph.prototype.resetZoom = function() {
1539 var dirty = false, dirtyX = false, dirtyY = false;
1540 if (this.dateWindow_ !== null) {
1541 dirty = true;
1542 dirtyX = true;
1543 }
1544
1545 for (var i = 0; i < this.axes_.length; i++) {
1546 if (typeof(this.axes_[i].valueWindow) !== 'undefined' && this.axes_[i].valueWindow !== null) {
1547 dirty = true;
1548 dirtyY = true;
1549 }
1550 }
1551
1552 // Clear any selection, since it's likely to be drawn in the wrong place.
1553 this.clearSelection();
1554
1555 if (dirty) {
1556 this.zoomed_x_ = false;
1557 this.zoomed_y_ = false;
1558
1559 var minDate = this.rawData_[0][0];
1560 var maxDate = this.rawData_[this.rawData_.length - 1][0];
1561
1562 // With only one frame, don't bother calculating extreme ranges.
1563 // TODO(danvk): merge this block w/ the code below.
1564 if (!this.attr_("animatedZooms")) {
1565 this.dateWindow_ = null;
1566 for (i = 0; i < this.axes_.length; i++) {
1567 if (this.axes_[i].valueWindow !== null) {
1568 delete this.axes_[i].valueWindow;
1569 }
1570 }
1571 this.drawGraph_();
1572 if (this.attr_("zoomCallback")) {
1573 this.attr_("zoomCallback")(minDate, maxDate, this.yAxisRanges());
1574 }
1575 return;
1576 }
1577
1578 var oldWindow=null, newWindow=null, oldValueRanges=null, newValueRanges=null;
1579 if (dirtyX) {
1580 oldWindow = this.xAxisRange();
1581 newWindow = [minDate, maxDate];
1582 }
1583
1584 if (dirtyY) {
1585 oldValueRanges = this.yAxisRanges();
1586 // TODO(danvk): this is pretty inefficient
1587 var packed = this.gatherDatasets_(this.rolledSeries_, null);
1588 var extremes = packed.extremes;
1589
1590 // this has the side-effect of modifying this.axes_.
1591 // this doesn't make much sense in this context, but it's convenient (we
1592 // need this.axes_[*].extremeValues) and not harmful since we'll be
1593 // calling drawGraph_ shortly, which clobbers these values.
1594 this.computeYAxisRanges_(extremes);
1595
1596 newValueRanges = [];
1597 for (i = 0; i < this.axes_.length; i++) {
1598 var axis = this.axes_[i];
1599 newValueRanges.push((axis.valueRange !== null &&
1600 axis.valueRange !== undefined) ?
1601 axis.valueRange : axis.extremeRange);
1602 }
1603 }
1604
1605 var that = this;
1606 this.doAnimatedZoom(oldWindow, newWindow, oldValueRanges, newValueRanges,
1607 function() {
1608 that.dateWindow_ = null;
1609 for (var i = 0; i < that.axes_.length; i++) {
1610 if (that.axes_[i].valueWindow !== null) {
1611 delete that.axes_[i].valueWindow;
1612 }
1613 }
1614 if (that.attr_("zoomCallback")) {
1615 that.attr_("zoomCallback")(minDate, maxDate, that.yAxisRanges());
1616 }
1617 });
1618 }
1619 };
1620
1621 /**
1622 * Combined animation logic for all zoom functions.
1623 * either the x parameters or y parameters may be null.
1624 * @private
1625 */
1626 Dygraph.prototype.doAnimatedZoom = function(oldXRange, newXRange, oldYRanges, newYRanges, callback) {
1627 var steps = this.attr_("animatedZooms") ? Dygraph.ANIMATION_STEPS : 1;
1628
1629 var windows = [];
1630 var valueRanges = [];
1631 var step, frac;
1632
1633 if (oldXRange !== null && newXRange !== null) {
1634 for (step = 1; step <= steps; step++) {
1635 frac = Dygraph.zoomAnimationFunction(step, steps);
1636 windows[step-1] = [oldXRange[0]*(1-frac) + frac*newXRange[0],
1637 oldXRange[1]*(1-frac) + frac*newXRange[1]];
1638 }
1639 }
1640
1641 if (oldYRanges !== null && newYRanges !== null) {
1642 for (step = 1; step <= steps; step++) {
1643 frac = Dygraph.zoomAnimationFunction(step, steps);
1644 var thisRange = [];
1645 for (var j = 0; j < this.axes_.length; j++) {
1646 thisRange.push([oldYRanges[j][0]*(1-frac) + frac*newYRanges[j][0],
1647 oldYRanges[j][1]*(1-frac) + frac*newYRanges[j][1]]);
1648 }
1649 valueRanges[step-1] = thisRange;
1650 }
1651 }
1652
1653 var that = this;
1654 Dygraph.repeatAndCleanup(function(step) {
1655 if (valueRanges.length) {
1656 for (var i = 0; i < that.axes_.length; i++) {
1657 var w = valueRanges[step][i];
1658 that.axes_[i].valueWindow = [w[0], w[1]];
1659 }
1660 }
1661 if (windows.length) {
1662 that.dateWindow_ = windows[step];
1663 }
1664 that.drawGraph_();
1665 }, steps, Dygraph.ANIMATION_DURATION / steps, callback);
1666 };
1667
1668 /**
1669 * Get the current graph's area object.
1670 *
1671 * Returns: {x, y, w, h}
1672 */
1673 Dygraph.prototype.getArea = function() {
1674 return this.plotter_.area;
1675 };
1676
1677 /**
1678 * Convert a mouse event to DOM coordinates relative to the graph origin.
1679 *
1680 * Returns a two-element array: [X, Y].
1681 */
1682 Dygraph.prototype.eventToDomCoords = function(event) {
1683 if (event.offsetX && event.offsetY) {
1684 return [ event.offsetX, event.offsetY ];
1685 } else {
1686 var canvasx = Dygraph.pageX(event) - Dygraph.findPosX(this.mouseEventElement_);
1687 var canvasy = Dygraph.pageY(event) - Dygraph.findPosY(this.mouseEventElement_);
1688 return [canvasx, canvasy];
1689 }
1690 };
1691
1692 /**
1693 * Given a canvas X coordinate, find the closest row.
1694 * @param {Number} domX graph-relative DOM X coordinate
1695 * Returns: row number, integer
1696 * @private
1697 */
1698 Dygraph.prototype.findClosestRow = function(domX) {
1699 var minDistX = Infinity;
1700 var pointIdx = -1, setIdx = -1;
1701 var sets = this.layout_.points;
1702 for (var i = 0; i < sets.length; i++) {
1703 var points = sets[i];
1704 var len = points.length;
1705 for (var j = 0; j < len; j++) {
1706 var point = points[j];
1707 if (!Dygraph.isValidPoint(point, true)) continue;
1708 var dist = Math.abs(point.canvasx - domX);
1709 if (dist < minDistX) {
1710 minDistX = dist;
1711 setIdx = i;
1712 pointIdx = j;
1713 }
1714 }
1715 }
1716
1717 // TODO(danvk): remove this function; it's trivial and has only one use.
1718 return this.idxToRow_(setIdx, pointIdx);
1719 };
1720
1721 /**
1722 * Given canvas X,Y coordinates, find the closest point.
1723 *
1724 * This finds the individual data point across all visible series
1725 * that's closest to the supplied DOM coordinates using the standard
1726 * Euclidean X,Y distance.
1727 *
1728 * @param {Number} domX graph-relative DOM X coordinate
1729 * @param {Number} domY graph-relative DOM Y coordinate
1730 * Returns: {row, seriesName, point}
1731 * @private
1732 */
1733 Dygraph.prototype.findClosestPoint = function(domX, domY) {
1734 var minDist = Infinity;
1735 var idx = -1;
1736 var dist, dx, dy, point, closestPoint, closestSeries;
1737 for ( var setIdx = this.layout_.points.length - 1 ; setIdx >= 0 ; --setIdx ) {
1738 var points = this.layout_.points[setIdx];
1739 for (var i = 0; i < points.length; ++i) {
1740 var point = points[i];
1741 if (!Dygraph.isValidPoint(point)) continue;
1742 dx = point.canvasx - domX;
1743 dy = point.canvasy - domY;
1744 dist = dx * dx + dy * dy;
1745 if (dist < minDist) {
1746 minDist = dist;
1747 closestPoint = point;
1748 closestSeries = setIdx;
1749 idx = i;
1750 }
1751 }
1752 }
1753 var name = this.layout_.setNames[closestSeries];
1754 return {
1755 row: idx + this.getLeftBoundary_(),
1756 seriesName: name,
1757 point: closestPoint
1758 };
1759 };
1760
1761 /**
1762 * Given canvas X,Y coordinates, find the touched area in a stacked graph.
1763 *
1764 * This first finds the X data point closest to the supplied DOM X coordinate,
1765 * then finds the series which puts the Y coordinate on top of its filled area,
1766 * using linear interpolation between adjacent point pairs.
1767 *
1768 * @param {Number} domX graph-relative DOM X coordinate
1769 * @param {Number} domY graph-relative DOM Y coordinate
1770 * Returns: {row, seriesName, point}
1771 * @private
1772 */
1773 Dygraph.prototype.findStackedPoint = function(domX, domY) {
1774 var row = this.findClosestRow(domX);
1775 var boundary = this.getLeftBoundary_();
1776 var rowIdx = row - boundary;
1777 var closestPoint, closestSeries;
1778 for (var setIdx = 0; setIdx < this.layout_.points.length; ++setIdx) {
1779 var points = this.layout_.points[setIdx];
1780 if (rowIdx >= points.length) continue;
1781 var p1 = points[rowIdx];
1782 if (!Dygraph.isValidPoint(p1)) continue;
1783 var py = p1.canvasy;
1784 if (domX > p1.canvasx && rowIdx + 1 < points.length) {
1785 // interpolate series Y value using next point
1786 var p2 = points[rowIdx + 1];
1787 if (Dygraph.isValidPoint(p2)) {
1788 var dx = p2.canvasx - p1.canvasx;
1789 if (dx > 0) {
1790 var r = (domX - p1.canvasx) / dx;
1791 py += r * (p2.canvasy - p1.canvasy);
1792 }
1793 }
1794 } else if (domX < p1.canvasx && rowIdx > 0) {
1795 // interpolate series Y value using previous point
1796 var p0 = points[rowIdx - 1];
1797 if (Dygraph.isValidPoint(p0)) {
1798 var dx = p1.canvasx - p0.canvasx;
1799 if (dx > 0) {
1800 var r = (p1.canvasx - domX) / dx;
1801 py += r * (p0.canvasy - p1.canvasy);
1802 }
1803 }
1804 }
1805 // Stop if the point (domX, py) is above this series' upper edge
1806 if (setIdx === 0 || py < domY) {
1807 closestPoint = p1;
1808 closestSeries = setIdx;
1809 }
1810 }
1811 var name = this.layout_.setNames[closestSeries];
1812 return {
1813 row: row,
1814 seriesName: name,
1815 point: closestPoint
1816 };
1817 };
1818
1819 /**
1820 * When the mouse moves in the canvas, display information about a nearby data
1821 * point and draw dots over those points in the data series. This function
1822 * takes care of cleanup of previously-drawn dots.
1823 * @param {Object} event The mousemove event from the browser.
1824 * @private
1825 */
1826 Dygraph.prototype.mouseMove_ = function(event) {
1827 // This prevents JS errors when mousing over the canvas before data loads.
1828 var points = this.layout_.points;
1829 if (points === undefined || points === null) return;
1830
1831 var canvasCoords = this.eventToDomCoords(event);
1832 var canvasx = canvasCoords[0];
1833 var canvasy = canvasCoords[1];
1834
1835 var highlightSeriesOpts = this.attr_("highlightSeriesOpts");
1836 var selectionChanged = false;
1837 if (highlightSeriesOpts && !this.isSeriesLocked()) {
1838 var closest;
1839 if (this.attr_("stackedGraph")) {
1840 closest = this.findStackedPoint(canvasx, canvasy);
1841 } else {
1842 closest = this.findClosestPoint(canvasx, canvasy);
1843 }
1844 selectionChanged = this.setSelection(closest.row, closest.seriesName);
1845 } else {
1846 var idx = this.findClosestRow(canvasx);
1847 selectionChanged = this.setSelection(idx);
1848 }
1849
1850 var callback = this.attr_("highlightCallback");
1851 if (callback && selectionChanged) {
1852 callback(event,
1853 this.lastx_,
1854 this.selPoints_,
1855 this.lastRow_ + this.getLeftBoundary_(),
1856 this.highlightSet_);
1857 }
1858 };
1859
1860 /**
1861 * Fetch left offset from first defined boundaryIds record (see bug #236).
1862 * @private
1863 */
1864 Dygraph.prototype.getLeftBoundary_ = function() {
1865 for (var i = 0; i < this.boundaryIds_.length; i++) {
1866 if (this.boundaryIds_[i] !== undefined) {
1867 return this.boundaryIds_[i][0];
1868 }
1869 }
1870 return 0;
1871 };
1872
1873 /**
1874 * Transforms layout_.points index into data row number.
1875 * @param int layout_.points index
1876 * @return int row number, or -1 if none could be found.
1877 * @private
1878 */
1879 Dygraph.prototype.idxToRow_ = function(setIdx, rowIdx) {
1880 if (rowIdx < 0) return -1;
1881
1882 var boundary = this.getLeftBoundary_();
1883 return boundary + rowIdx;
1884 };
1885
1886 Dygraph.prototype.animateSelection_ = function(direction) {
1887 var totalSteps = 10;
1888 var millis = 30;
1889 if (this.fadeLevel === undefined) this.fadeLevel = 0;
1890 if (this.animateId === undefined) this.animateId = 0;
1891 var start = this.fadeLevel;
1892 var steps = direction < 0 ? start : totalSteps - start;
1893 if (steps <= 0) {
1894 if (this.fadeLevel) {
1895 this.updateSelection_(1.0);
1896 }
1897 return;
1898 }
1899
1900 var thisId = ++this.animateId;
1901 var that = this;
1902 Dygraph.repeatAndCleanup(
1903 function(n) {
1904 // ignore simultaneous animations
1905 if (that.animateId != thisId) return;
1906
1907 that.fadeLevel += direction;
1908 if (that.fadeLevel === 0) {
1909 that.clearSelection();
1910 } else {
1911 that.updateSelection_(that.fadeLevel / totalSteps);
1912 }
1913 },
1914 steps, millis, function() {});
1915 };
1916
1917 /**
1918 * Draw dots over the selectied points in the data series. This function
1919 * takes care of cleanup of previously-drawn dots.
1920 * @private
1921 */
1922 Dygraph.prototype.updateSelection_ = function(opt_animFraction) {
1923 /*var defaultPrevented = */
1924 this.cascadeEvents_('select', {
1925 selectedX: this.lastx_,
1926 selectedPoints: this.selPoints_
1927 });
1928 // TODO(danvk): use defaultPrevented here?
1929
1930 // Clear the previously drawn vertical, if there is one
1931 var i;
1932 var ctx = this.canvas_ctx_;
1933 if (this.attr_('highlightSeriesOpts')) {
1934 ctx.clearRect(0, 0, this.width_, this.height_);
1935 var alpha = 1.0 - this.attr_('highlightSeriesBackgroundAlpha');
1936 if (alpha) {
1937 // Activating background fade includes an animation effect for a gradual
1938 // fade. TODO(klausw): make this independently configurable if it causes
1939 // issues? Use a shared preference to control animations?
1940 var animateBackgroundFade = true;
1941 if (animateBackgroundFade) {
1942 if (opt_animFraction === undefined) {
1943 // start a new animation
1944 this.animateSelection_(1);
1945 return;
1946 }
1947 alpha *= opt_animFraction;
1948 }
1949 ctx.fillStyle = 'rgba(255,255,255,' + alpha + ')';
1950 ctx.fillRect(0, 0, this.width_, this.height_);
1951 }
1952
1953 // Redraw only the highlighted series in the interactive canvas (not the
1954 // static plot canvas, which is where series are usually drawn).
1955 this.plotter_._renderLineChart(this.highlightSet_, ctx);
1956 } else if (this.previousVerticalX_ >= 0) {
1957 // Determine the maximum highlight circle size.
1958 var maxCircleSize = 0;
1959 var labels = this.attr_('labels');
1960 for (i = 1; i < labels.length; i++) {
1961 var r = this.attr_('highlightCircleSize', labels[i]);
1962 if (r > maxCircleSize) maxCircleSize = r;
1963 }
1964 var px = this.previousVerticalX_;
1965 ctx.clearRect(px - maxCircleSize - 1, 0,
1966 2 * maxCircleSize + 2, this.height_);
1967 }
1968
1969 if (this.isUsingExcanvas_ && this.currentZoomRectArgs_) {
1970 Dygraph.prototype.drawZoomRect_.apply(this, this.currentZoomRectArgs_);
1971 }
1972
1973 if (this.selPoints_.length > 0) {
1974 // Draw colored circles over the center of each selected point
1975 var canvasx = this.selPoints_[0].canvasx;
1976 ctx.save();
1977 for (i = 0; i < this.selPoints_.length; i++) {
1978 var pt = this.selPoints_[i];
1979 if (!Dygraph.isOK(pt.canvasy)) continue;
1980
1981 var circleSize = this.attr_('highlightCircleSize', pt.name);
1982 var callback = this.attr_("drawHighlightPointCallback", pt.name);
1983 var color = this.plotter_.colors[pt.name];
1984 if (!callback) {
1985 callback = Dygraph.Circles.DEFAULT;
1986 }
1987 ctx.lineWidth = this.attr_('strokeWidth', pt.name);
1988 ctx.strokeStyle = color;
1989 ctx.fillStyle = color;
1990 callback(this.g, pt.name, ctx, canvasx, pt.canvasy,
1991 color, circleSize, pt.idx);
1992 }
1993 ctx.restore();
1994
1995 this.previousVerticalX_ = canvasx;
1996 }
1997 };
1998
1999 /**
2000 * Manually set the selected points and display information about them in the
2001 * legend. The selection can be cleared using clearSelection() and queried
2002 * using getSelection().
2003 * @param { Integer } row number that should be highlighted (i.e. appear with
2004 * hover dots on the chart). Set to false to clear any selection.
2005 * @param { seriesName } optional series name to highlight that series with the
2006 * the highlightSeriesOpts setting.
2007 * @param { locked } optional If true, keep seriesName selected when mousing
2008 * over the graph, disabling closest-series highlighting. Call clearSelection()
2009 * to unlock it.
2010 */
2011 Dygraph.prototype.setSelection = function(row, opt_seriesName, opt_locked) {
2012 // Extract the points we've selected
2013 this.selPoints_ = [];
2014
2015 if (row !== false) {
2016 row -= this.getLeftBoundary_();
2017 }
2018
2019 var changed = false;
2020 if (row !== false && row >= 0) {
2021 if (row != this.lastRow_) changed = true;
2022 this.lastRow_ = row;
2023 for (var setIdx = 0; setIdx < this.layout_.points.length; ++setIdx) {
2024 var points = this.layout_.points[setIdx];
2025 if (row < points.length) {
2026 var point = points[row];
2027 if (point.yval !== null) this.selPoints_.push(point);
2028 }
2029 }
2030 } else {
2031 if (this.lastRow_ >= 0) changed = true;
2032 this.lastRow_ = -1;
2033 }
2034
2035 if (this.selPoints_.length) {
2036 this.lastx_ = this.selPoints_[0].xval;
2037 } else {
2038 this.lastx_ = -1;
2039 }
2040
2041 if (opt_seriesName !== undefined) {
2042 if (this.highlightSet_ !== opt_seriesName) changed = true;
2043 this.highlightSet_ = opt_seriesName;
2044 }
2045
2046 if (opt_locked !== undefined) {
2047 this.lockedSet_ = opt_locked;
2048 }
2049
2050 if (changed) {
2051 this.updateSelection_(undefined);
2052 }
2053 return changed;
2054 };
2055
2056 /**
2057 * The mouse has left the canvas. Clear out whatever artifacts remain
2058 * @param {Object} event the mouseout event from the browser.
2059 * @private
2060 */
2061 Dygraph.prototype.mouseOut_ = function(event) {
2062 if (this.attr_("unhighlightCallback")) {
2063 this.attr_("unhighlightCallback")(event);
2064 }
2065
2066 if (this.attr_("hideOverlayOnMouseOut") && !this.lockedSet_) {
2067 this.clearSelection();
2068 }
2069 };
2070
2071 /**
2072 * Clears the current selection (i.e. points that were highlighted by moving
2073 * the mouse over the chart).
2074 */
2075 Dygraph.prototype.clearSelection = function() {
2076 this.cascadeEvents_('deselect', {});
2077
2078 this.lockedSet_ = false;
2079 // Get rid of the overlay data
2080 if (this.fadeLevel) {
2081 this.animateSelection_(-1);
2082 return;
2083 }
2084 this.canvas_ctx_.clearRect(0, 0, this.width_, this.height_);
2085 this.fadeLevel = 0;
2086 this.selPoints_ = [];
2087 this.lastx_ = -1;
2088 this.lastRow_ = -1;
2089 this.highlightSet_ = null;
2090 };
2091
2092 /**
2093 * Returns the number of the currently selected row. To get data for this row,
2094 * you can use the getValue method.
2095 * @return { Integer } row number, or -1 if nothing is selected
2096 */
2097 Dygraph.prototype.getSelection = function() {
2098 if (!this.selPoints_ || this.selPoints_.length < 1) {
2099 return -1;
2100 }
2101
2102 for (var setIdx = 0; setIdx < this.layout_.points.length; setIdx++) {
2103 var points = this.layout_.points[setIdx];
2104 for (var row = 0; row < points.length; row++) {
2105 if (points[row].x == this.selPoints_[0].x) {
2106 return row + this.getLeftBoundary_();
2107 }
2108 }
2109 }
2110 return -1;
2111 };
2112
2113 /**
2114 * Returns the name of the currently-highlighted series.
2115 * Only available when the highlightSeriesOpts option is in use.
2116 */
2117 Dygraph.prototype.getHighlightSeries = function() {
2118 return this.highlightSet_;
2119 };
2120
2121 /**
2122 * Returns true if the currently-highlighted series was locked
2123 * via setSelection(..., seriesName, true).
2124 */
2125 Dygraph.prototype.isSeriesLocked = function() {
2126 return this.lockedSet_;
2127 };
2128
2129 /**
2130 * Fires when there's data available to be graphed.
2131 * @param {String} data Raw CSV data to be plotted
2132 * @private
2133 */
2134 Dygraph.prototype.loadedEvent_ = function(data) {
2135 this.rawData_ = this.parseCSV_(data);
2136 this.predraw_();
2137 };
2138
2139 /**
2140 * Add ticks on the x-axis representing years, months, quarters, weeks, or days
2141 * @private
2142 */
2143 Dygraph.prototype.addXTicks_ = function() {
2144 // Determine the correct ticks scale on the x-axis: quarterly, monthly, ...
2145 var range;
2146 if (this.dateWindow_) {
2147 range = [this.dateWindow_[0], this.dateWindow_[1]];
2148 } else {
2149 range = this.xAxisExtremes();
2150 }
2151
2152 var xAxisOptionsView = this.optionsViewForAxis_('x');
2153 var xTicks = xAxisOptionsView('ticker')(
2154 range[0],
2155 range[1],
2156 this.width_, // TODO(danvk): should be area.width
2157 xAxisOptionsView,
2158 this);
2159 // var msg = 'ticker(' + range[0] + ', ' + range[1] + ', ' + this.width_ + ', ' + this.attr_('pixelsPerXLabel') + ') -> ' + JSON.stringify(xTicks);
2160 // console.log(msg);
2161 this.layout_.setXTicks(xTicks);
2162 };
2163
2164 /**
2165 * @private
2166 * Computes the range of the data series (including confidence intervals).
2167 * @param { [Array] } series either [ [x1, y1], [x2, y2], ... ] or
2168 * [ [x1, [y1, dev_low, dev_high]], [x2, [y2, dev_low, dev_high]], ...
2169 * @return [low, high]
2170 */
2171 Dygraph.prototype.extremeValues_ = function(series) {
2172 var minY = null, maxY = null, j, y;
2173
2174 var bars = this.attr_("errorBars") || this.attr_("customBars");
2175 if (bars) {
2176 // With custom bars, maxY is the max of the high values.
2177 for (j = 0; j < series.length; j++) {
2178 y = series[j][1][0];
2179 if (y === null || isNaN(y)) continue;
2180 var low = y - series[j][1][1];
2181 var high = y + series[j][1][2];
2182 if (low > y) low = y; // this can happen with custom bars,
2183 if (high < y) high = y; // e.g. in tests/custom-bars.html
2184 if (maxY === null || high > maxY) {
2185 maxY = high;
2186 }
2187 if (minY === null || low < minY) {
2188 minY = low;
2189 }
2190 }
2191 } else {
2192 for (j = 0; j < series.length; j++) {
2193 y = series[j][1];
2194 if (y === null || isNaN(y)) continue;
2195 if (maxY === null || y > maxY) {
2196 maxY = y;
2197 }
2198 if (minY === null || y < minY) {
2199 minY = y;
2200 }
2201 }
2202 }
2203
2204 return [minY, maxY];
2205 };
2206
2207 /**
2208 * @private
2209 * This function is called once when the chart's data is changed or the options
2210 * dictionary is updated. It is _not_ called when the user pans or zooms. The
2211 * idea is that values derived from the chart's data can be computed here,
2212 * rather than every time the chart is drawn. This includes things like the
2213 * number of axes, rolling averages, etc.
2214 */
2215 Dygraph.prototype.predraw_ = function() {
2216 var start = new Date();
2217
2218 this.layout_.computePlotArea();
2219
2220 // TODO(danvk): move more computations out of drawGraph_ and into here.
2221 this.computeYAxes_();
2222
2223 // Create a new plotter.
2224 if (this.plotter_) {
2225 this.cascadeEvents_('clearChart');
2226 this.plotter_.clear();
2227 }
2228
2229 if(!this.is_initial_draw_) {
2230 this.canvas_ctx_.restore();
2231 this.hidden_ctx_.restore();
2232 }
2233
2234 this.canvas_ctx_.save();
2235 this.hidden_ctx_.save();
2236
2237 this.plotter_ = new DygraphCanvasRenderer(this,
2238 this.hidden_,
2239 this.hidden_ctx_,
2240 this.layout_);
2241
2242 // The roller sits in the bottom left corner of the chart. We don't know where
2243 // this will be until the options are available, so it's positioned here.
2244 this.createRollInterface_();
2245
2246 this.cascadeEvents_('predraw');
2247
2248 // Convert the raw data (a 2D array) into the internal format and compute
2249 // rolling averages.
2250 this.rolledSeries_ = [null]; // x-axis is the first series and it's special
2251 for (var i = 1; i < this.numColumns(); i++) {
2252 // var logScale = this.attr_('logscale', i); // TODO(klausw): this looks wrong // konigsberg thinks so too.
2253 var logScale = this.attr_('logscale');
2254 var series = this.extractSeries_(this.rawData_, i, logScale);
2255 series = this.rollingAverage(series, this.rollPeriod_);
2256 this.rolledSeries_.push(series);
2257 }
2258
2259 // If the data or options have changed, then we'd better redraw.
2260 this.drawGraph_();
2261
2262 // This is used to determine whether to do various animations.
2263 var end = new Date();
2264 this.drawingTimeMs_ = (end - start);
2265 };
2266
2267 /**
2268 * Point structure.
2269 *
2270 * xval_* and yval_* are the original unscaled data values,
2271 * while x_* and y_* are scaled to the range (0.0-1.0) for plotting.
2272 * yval_stacked is the cumulative Y value used for stacking graphs,
2273 * and bottom/top/minus/plus are used for error bar graphs.
2274 *
2275 * @typedef {{
2276 * idx: number,
2277 * name: string,
2278 * x: ?number,
2279 * xval: ?number,
2280 * y_bottom: ?number,
2281 * y: ?number,
2282 * y_stacked: ?number,
2283 * y_top: ?number,
2284 * yval_minus: ?number,
2285 * yval: ?number,
2286 * yval_plus: ?number,
2287 * yval_stacked
2288 * }}
2289 */
2290 Dygraph.PointType = undefined;
2291
2292 // TODO(bhs): these loops are a hot-spot for high-point-count charts. In fact,
2293 // on chrome+linux, they are 6 times more expensive than iterating through the
2294 // points and drawing the lines. The brunt of the cost comes from allocating
2295 // the |point| structures.
2296 /**
2297 * Converts a series to a Point array.
2298 *
2299 * @param {Array.<Array.<(?number|Array<?number>)>} series Array where
2300 * series[row] = [x,y] or [x, [y, err]] or [x, [y, yplus, yminus]].
2301 * @param {boolean} bars True if error bars or custom bars are being drawn.
2302 * @param {string} setName Name of the series.
2303 * @param {number} boundaryIdStart Index offset of the first point, equal to
2304 * the number of skipped points left of the date window minimum (if any).
2305 * @return {Array.<Dygraph.PointType>} List of points for this series.
2306 */
2307 Dygraph.seriesToPoints_ = function(series, bars, setName, boundaryIdStart) {
2308 var points = [];
2309 for (var i = 0; i < series.length; ++i) {
2310 var item = series[i];
2311 var yraw = bars ? item[1][0] : item[1];
2312 var yval = yraw === null ? null : DygraphLayout.parseFloat_(yraw);
2313 var point = {
2314 x: NaN,
2315 y: NaN,
2316 xval: DygraphLayout.parseFloat_(item[0]),
2317 yval: yval,
2318 name: setName, // TODO(danvk): is this really necessary?
2319 idx: i + boundaryIdStart
2320 };
2321
2322 if (bars) {
2323 point.y_top = NaN;
2324 point.y_bottom = NaN;
2325 point.yval_minus = DygraphLayout.parseFloat_(item[1][1]);
2326 point.yval_plus = DygraphLayout.parseFloat_(item[1][2]);
2327 }
2328 points.push(point);
2329 }
2330 return points;
2331 };
2332
2333
2334 /**
2335 * Calculates point stacking for stackedGraph=true.
2336 *
2337 * For stacking purposes, interpolate or extend neighboring data across
2338 * NaN values based on stackedGraphNaNFill settings. This is for display
2339 * only, the underlying data value as shown in the legend remains NaN.
2340 *
2341 * @param {Array.<Dygraph.PointType>} points Point array for a single series.
2342 * Updates each Point's yval_stacked property.
2343 * @param {Array.<number>} cumulativeYval Accumulated top-of-graph stacked Y
2344 * values for the series seen so far. Index is the row number. Updated
2345 * based on the current series's values.
2346 * @param {Array.<number>} seriesExtremes Min and max values, updated
2347 * to reflect the stacked values.
2348 * @param {string} fillMethod Interpolation method, one of 'all', 'inside', or
2349 * 'none'.
2350 */
2351 Dygraph.stackPoints_ = function(
2352 points, cumulativeYval, seriesExtremes, fillMethod) {
2353 var lastXval = null;
2354 var prevPoint = null;
2355 var nextPoint = null;
2356 var nextPointIdx = -1;
2357
2358 // Find the next stackable point starting from the given index.
2359 var updateNextPoint = function(idx) {
2360 // If we've previously found a non-NaN point and haven't gone past it yet,
2361 // just use that.
2362 if (nextPointIdx >= idx) return;
2363
2364 // We haven't found a non-NaN point yet or have moved past it,
2365 // look towards the right to find a non-NaN point.
2366 for (var j = idx; j < points.length; ++j) {
2367 // Clear out a previously-found point (if any) since it's no longer
2368 // valid, we shouldn't use it for interpolation anymore.
2369 nextPoint = null;
2370 if (!isNaN(points[j].yval) && points[j].yval !== null) {
2371 nextPointIdx = j;
2372 nextPoint = points[j];
2373 break;
2374 }
2375 }
2376 };
2377
2378 for (var i = 0; i < points.length; ++i) {
2379 var point = points[i];
2380 var xval = point.xval;
2381 if (cumulativeYval[xval] === undefined) {
2382 cumulativeYval[xval] = 0;
2383 }
2384
2385 var actualYval = point.yval;
2386 if (isNaN(actualYval) || actualYval === null) {
2387 // Interpolate/extend for stacking purposes if possible.
2388 updateNextPoint(i);
2389 if (prevPoint && nextPoint && fillMethod != 'none') {
2390 // Use linear interpolation between prevPoint and nextPoint.
2391 actualYval = prevPoint.yval + (nextPoint.yval - prevPoint.yval) *
2392 ((xval - prevPoint.xval) / (nextPoint.xval - prevPoint.xval));
2393 } else if (prevPoint && fillMethod == 'all') {
2394 actualYval = prevPoint.yval;
2395 } else if (nextPoint && fillMethod == 'all') {
2396 actualYval = nextPoint.yval;
2397 } else {
2398 actualYval = 0;
2399 }
2400 } else {
2401 prevPoint = point;
2402 }
2403
2404 var stackedYval = cumulativeYval[xval];
2405 if (lastXval != xval) {
2406 // If an x-value is repeated, we ignore the duplicates.
2407 stackedYval += actualYval;
2408 cumulativeYval[xval] = stackedYval;
2409 }
2410 lastXval = xval;
2411
2412 point.yval_stacked = stackedYval;
2413
2414 if (stackedYval > seriesExtremes[1]) {
2415 seriesExtremes[1] = stackedYval;
2416 }
2417 if (stackedYval < seriesExtremes[0]) {
2418 seriesExtremes[0] = stackedYval;
2419 }
2420 }
2421 };
2422
2423
2424 /**
2425 * Loop over all fields and create datasets, calculating extreme y-values for
2426 * each series and extreme x-indices as we go.
2427 *
2428 * dateWindow is passed in as an explicit parameter so that we can compute
2429 * extreme values "speculatively", i.e. without actually setting state on the
2430 * dygraph.
2431 *
2432 * @param {Array.<Array.<Array.<(number|Array<number>)>>} rolledSeries, where
2433 * rolledSeries[seriesIndex][row] = raw point, where
2434 * seriesIndex is the column number starting with 1, and
2435 * rawPoint is [x,y] or [x, [y, err]] or [x, [y, yminus, yplus]].
2436 * @param {?Array.<number>} dateWindow [xmin, xmax] pair, or null.
2437 * @return {{
2438 * points: Array.<Array.<Dygraph.PointType>>,
2439 * seriesExtremes: Array.<Array.<number>>,
2440 * boundaryIds: Array.<number>}}
2441 * @private
2442 */
2443 Dygraph.prototype.gatherDatasets_ = function(rolledSeries, dateWindow) {
2444 var boundaryIds = [];
2445 var points = [];
2446 var cumulativeYval = []; // For stacked series.
2447 var extremes = {}; // series name -> [low, high]
2448 var i, k;
2449 var errorBars = this.attr_("errorBars");
2450 var customBars = this.attr_("customBars");
2451 var bars = errorBars || customBars;
2452 var isValueNull = function(sample) {
2453 if (!bars) {
2454 return sample[1] === null;
2455 } else {
2456 return customBars ? sample[1][1] === null :
2457 errorBars ? sample[1][0] === null : false;
2458 }
2459 };
2460
2461 // Loop over the fields (series). Go from the last to the first,
2462 // because if they're stacked that's how we accumulate the values.
2463 var num_series = rolledSeries.length - 1;
2464 var series;
2465 for (i = num_series; i >= 1; i--) {
2466 if (!this.visibility()[i - 1]) continue;
2467
2468 // Prune down to the desired range, if necessary (for zooming)
2469 // Because there can be lines going to points outside of the visible area,
2470 // we actually prune to visible points, plus one on either side.
2471 if (dateWindow) {
2472 series = rolledSeries[i];
2473 var low = dateWindow[0];
2474 var high = dateWindow[1];
2475
2476 // TODO(danvk): do binary search instead of linear search.
2477 // TODO(danvk): pass firstIdx and lastIdx directly to the renderer.
2478 var firstIdx = null, lastIdx = null;
2479 for (k = 0; k < series.length; k++) {
2480 if (series[k][0] >= low && firstIdx === null) {
2481 firstIdx = k;
2482 }
2483 if (series[k][0] <= high) {
2484 lastIdx = k;
2485 }
2486 }
2487
2488 if (firstIdx === null) firstIdx = 0;
2489 var correctedFirstIdx = firstIdx;
2490 var isInvalidValue = true;
2491 while (isInvalidValue && correctedFirstIdx > 0) {
2492 correctedFirstIdx--;
2493 isInvalidValue = isValueNull(series[correctedFirstIdx]);
2494 }
2495
2496 if (lastIdx === null) lastIdx = series.length - 1;
2497 var correctedLastIdx = lastIdx;
2498 isInvalidValue = true;
2499 while (isInvalidValue && correctedLastIdx < series.length - 1) {
2500 correctedLastIdx++;
2501 isInvalidValue = isValueNull(series[correctedLastIdx]);
2502 }
2503
2504 boundaryIds[i-1] = [(firstIdx > 0) ? firstIdx - 1 : firstIdx,
2505 (lastIdx < series.length - 1) ? lastIdx + 1 : lastIdx];
2506
2507 if (correctedFirstIdx!==firstIdx) {
2508 firstIdx = correctedFirstIdx;
2509 }
2510 if (correctedLastIdx !== lastIdx) {
2511 lastIdx = correctedLastIdx;
2512 }
2513 // .slice's end is exclusive, we want to include lastIdx.
2514 series = series.slice(firstIdx, lastIdx + 1);
2515 } else {
2516 series = rolledSeries[i];
2517 boundaryIds[i-1] = [0, series.length-1];
2518 }
2519
2520 var seriesName = this.attr_("labels")[i];
2521 var seriesExtremes = this.extremeValues_(series);
2522
2523 var seriesPoints = Dygraph.seriesToPoints_(
2524 series, bars, seriesName, boundaryIds[i-1][0]);
2525
2526 if (this.attr_("stackedGraph")) {
2527 Dygraph.stackPoints_(seriesPoints, cumulativeYval, seriesExtremes,
2528 this.attr_("stackedGraphNaNFill"));
2529 }
2530
2531 extremes[seriesName] = seriesExtremes;
2532 points[i] = seriesPoints;
2533 }
2534
2535 return { points: points, extremes: extremes, boundaryIds: boundaryIds };
2536 };
2537
2538 /**
2539 * Update the graph with new data. This method is called when the viewing area
2540 * has changed. If the underlying data or options have changed, predraw_ will
2541 * be called before drawGraph_ is called.
2542 *
2543 * @private
2544 */
2545 Dygraph.prototype.drawGraph_ = function() {
2546 var start = new Date();
2547
2548 // This is used to set the second parameter to drawCallback, below.
2549 var is_initial_draw = this.is_initial_draw_;
2550 this.is_initial_draw_ = false;
2551
2552 this.layout_.removeAllDatasets();
2553 this.setColors_();
2554 this.attrs_.pointSize = 0.5 * this.attr_('highlightCircleSize');
2555
2556 var packed = this.gatherDatasets_(this.rolledSeries_, this.dateWindow_);
2557 var points = packed.points;
2558 var extremes = packed.extremes;
2559 this.boundaryIds_ = packed.boundaryIds;
2560
2561 this.setIndexByName_ = {};
2562 var labels = this.attr_("labels");
2563 if (labels.length > 0) {
2564 this.setIndexByName_[labels[0]] = 0;
2565 }
2566 var dataIdx = 0;
2567 for (var i = 1; i < points.length; i++) {
2568 this.setIndexByName_[labels[i]] = i;
2569 if (!this.visibility()[i - 1]) continue;
2570 this.layout_.addDataset(labels[i], points[i]);
2571 this.datasetIndex_[i] = dataIdx++;
2572 }
2573
2574 this.computeYAxisRanges_(extremes);
2575 this.layout_.setYAxes(this.axes_);
2576
2577 this.addXTicks_();
2578
2579 // Save the X axis zoomed status as the updateOptions call will tend to set it erroneously
2580 var tmp_zoomed_x = this.zoomed_x_;
2581 // Tell PlotKit to use this new data and render itself
2582 this.zoomed_x_ = tmp_zoomed_x;
2583 this.layout_.evaluate();
2584 this.renderGraph_(is_initial_draw);
2585
2586 if (this.attr_("timingName")) {
2587 var end = new Date();
2588 Dygraph.info(this.attr_("timingName") + " - drawGraph: " + (end - start) + "ms");
2589 }
2590 };
2591
2592 /**
2593 * This does the work of drawing the chart. It assumes that the layout and axis
2594 * scales have already been set (e.g. by predraw_).
2595 *
2596 * @private
2597 */
2598 Dygraph.prototype.renderGraph_ = function(is_initial_draw) {
2599 this.cascadeEvents_('clearChart');
2600 this.plotter_.clear();
2601
2602 if (this.attr_('underlayCallback')) {
2603 // NOTE: we pass the dygraph object to this callback twice to avoid breaking
2604 // users who expect a deprecated form of this callback.
2605 this.attr_('underlayCallback')(
2606 this.hidden_ctx_, this.layout_.getPlotArea(), this, this);
2607 }
2608
2609 var e = {
2610 canvas: this.hidden_,
2611 drawingContext: this.hidden_ctx_
2612 };
2613 this.cascadeEvents_('willDrawChart', e);
2614 this.plotter_.render();
2615 this.cascadeEvents_('didDrawChart', e);
2616 this.lastRow_ = -1; // because plugins/legend.js clears the legend
2617
2618 // TODO(danvk): is this a performance bottleneck when panning?
2619 // The interaction canvas should already be empty in that situation.
2620 this.canvas_.getContext('2d').clearRect(0, 0, this.canvas_.width,
2621 this.canvas_.height);
2622
2623 if (this.attr_("drawCallback") !== null) {
2624 this.attr_("drawCallback")(this, is_initial_draw);
2625 }
2626 };
2627
2628 /**
2629 * @private
2630 * Determine properties of the y-axes which are independent of the data
2631 * currently being displayed. This includes things like the number of axes and
2632 * the style of the axes. It does not include the range of each axis and its
2633 * tick marks.
2634 * This fills in this.axes_.
2635 * axes_ = [ { options } ]
2636 * indices are into the axes_ array.
2637 */
2638 Dygraph.prototype.computeYAxes_ = function() {
2639 // Preserve valueWindow settings if they exist, and if the user hasn't
2640 // specified a new valueRange.
2641 var valueWindows, axis, index, opts, v;
2642 if (this.axes_ !== undefined && this.user_attrs_.hasOwnProperty("valueRange") === false) {
2643 valueWindows = [];
2644 for (index = 0; index < this.axes_.length; index++) {
2645 valueWindows.push(this.axes_[index].valueWindow);
2646 }
2647 }
2648
2649 // this.axes_ doesn't match this.attributes_.axes_.options. It's used for
2650 // data computation as well as options storage.
2651 // Go through once and add all the axes.
2652 this.axes_ = [];
2653
2654 for (axis = 0; axis < this.attributes_.numAxes(); axis++) {
2655 // Add a new axis, making a copy of its per-axis options.
2656 opts = { g : this };
2657 Dygraph.update(opts, this.attributes_.axisOptions(axis));
2658 this.axes_[axis] = opts;
2659 }
2660
2661
2662 // Copy global valueRange option over to the first axis.
2663 // NOTE(konigsberg): Are these two statements necessary?
2664 // I tried removing it. The automated tests pass, and manually
2665 // messing with tests/zoom.html showed no trouble.
2666 v = this.attr_('valueRange');
2667 if (v) this.axes_[0].valueRange = v;
2668
2669 if (valueWindows !== undefined) {
2670 // Restore valueWindow settings.
2671
2672 // When going from two axes back to one, we only restore
2673 // one axis.
2674 var idxCount = Math.min(valueWindows.length, this.axes_.length);
2675
2676 for (index = 0; index < idxCount; index++) {
2677 this.axes_[index].valueWindow = valueWindows[index];
2678 }
2679 }
2680
2681 for (axis = 0; axis < this.axes_.length; axis++) {
2682 if (axis === 0) {
2683 opts = this.optionsViewForAxis_('y' + (axis ? '2' : ''));
2684 v = opts("valueRange");
2685 if (v) this.axes_[axis].valueRange = v;
2686 } else { // To keep old behavior
2687 var axes = this.user_attrs_.axes;
2688 if (axes && axes.y2) {
2689 v = axes.y2.valueRange;
2690 if (v) this.axes_[axis].valueRange = v;
2691 }
2692 }
2693 }
2694 };
2695
2696 /**
2697 * Returns the number of y-axes on the chart.
2698 * @return {Number} the number of axes.
2699 */
2700 Dygraph.prototype.numAxes = function() {
2701 return this.attributes_.numAxes();
2702 };
2703
2704 /**
2705 * @private
2706 * Returns axis properties for the given series.
2707 * @param { String } setName The name of the series for which to get axis
2708 * properties, e.g. 'Y1'.
2709 * @return { Object } The axis properties.
2710 */
2711 Dygraph.prototype.axisPropertiesForSeries = function(series) {
2712 // TODO(danvk): handle errors.
2713 return this.axes_[this.attributes_.axisForSeries(series)];
2714 };
2715
2716 /**
2717 * @private
2718 * Determine the value range and tick marks for each axis.
2719 * @param {Object} extremes A mapping from seriesName -> [low, high]
2720 * This fills in the valueRange and ticks fields in each entry of this.axes_.
2721 */
2722 Dygraph.prototype.computeYAxisRanges_ = function(extremes) {
2723 var isNullUndefinedOrNaN = function(num) {
2724 return isNaN(parseFloat(num));
2725 };
2726 var numAxes = this.attributes_.numAxes();
2727 var ypadCompat, span, series, ypad;
2728
2729 var p_axis;
2730
2731 // Compute extreme values, a span and tick marks for each axis.
2732 for (var i = 0; i < numAxes; i++) {
2733 var axis = this.axes_[i];
2734 var logscale = this.attributes_.getForAxis("logscale", i);
2735 var includeZero = this.attributes_.getForAxis("includeZero", i);
2736 var independentTicks = this.attributes_.getForAxis("independentTicks", i);
2737 series = this.attributes_.seriesForAxis(i);
2738
2739 // Add some padding. This supports two Y padding operation modes:
2740 //
2741 // - backwards compatible (yRangePad not set):
2742 // 10% padding for automatic Y ranges, but not for user-supplied
2743 // ranges, and move a close-to-zero edge to zero except if
2744 // avoidMinZero is set, since drawing at the edge results in
2745 // invisible lines. Unfortunately lines drawn at the edge of a
2746 // user-supplied range will still be invisible. If logscale is
2747 // set, add a variable amount of padding at the top but
2748 // none at the bottom.
2749 //
2750 // - new-style (yRangePad set by the user):
2751 // always add the specified Y padding.
2752 //
2753 ypadCompat = true;
2754 ypad = 0.1; // add 10%
2755 if (this.attr_('yRangePad') !== null) {
2756 ypadCompat = false;
2757 // Convert pixel padding to ratio
2758 ypad = this.attr_('yRangePad') / this.plotter_.area.h;
2759 }
2760
2761 if (series.length === 0) {
2762 // If no series are defined or visible then use a reasonable default
2763 axis.extremeRange = [0, 1];
2764 } else {
2765 // Calculate the extremes of extremes.
2766 var minY = Infinity; // extremes[series[0]][0];
2767 var maxY = -Infinity; // extremes[series[0]][1];
2768 var extremeMinY, extremeMaxY;
2769
2770 for (var j = 0; j < series.length; j++) {
2771 // this skips invisible series
2772 if (!extremes.hasOwnProperty(series[j])) continue;
2773
2774 // Only use valid extremes to stop null data series' from corrupting the scale.
2775 extremeMinY = extremes[series[j]][0];
2776 if (extremeMinY !== null) {
2777 minY = Math.min(extremeMinY, minY);
2778 }
2779 extremeMaxY = extremes[series[j]][1];
2780 if (extremeMaxY !== null) {
2781 maxY = Math.max(extremeMaxY, maxY);
2782 }
2783 }
2784
2785 // Include zero if requested by the user.
2786 if (includeZero && !logscale) {
2787 if (minY > 0) minY = 0;
2788 if (maxY < 0) maxY = 0;
2789 }
2790
2791 // Ensure we have a valid scale, otherwise default to [0, 1] for safety.
2792 if (minY == Infinity) minY = 0;
2793 if (maxY == -Infinity) maxY = 1;
2794
2795 span = maxY - minY;
2796 // special case: if we have no sense of scale, center on the sole value.
2797 if (span === 0) {
2798 if (maxY !== 0) {
2799 span = Math.abs(maxY);
2800 } else {
2801 // ... and if the sole value is zero, use range 0-1.
2802 maxY = 1;
2803 span = 1;
2804 }
2805 }
2806
2807 var maxAxisY, minAxisY;
2808 if (logscale) {
2809 if (ypadCompat) {
2810 maxAxisY = maxY + ypad * span;
2811 minAxisY = minY;
2812 } else {
2813 var logpad = Math.exp(Math.log(span) * ypad);
2814 maxAxisY = maxY * logpad;
2815 minAxisY = minY / logpad;
2816 }
2817 } else {
2818 maxAxisY = maxY + ypad * span;
2819 minAxisY = minY - ypad * span;
2820
2821 // Backwards-compatible behavior: Move the span to start or end at zero if it's
2822 // close to zero, but not if avoidMinZero is set.
2823 if (ypadCompat && !this.attr_("avoidMinZero")) {
2824 if (minAxisY < 0 && minY >= 0) minAxisY = 0;
2825 if (maxAxisY > 0 && maxY <= 0) maxAxisY = 0;
2826 }
2827 }
2828 axis.extremeRange = [minAxisY, maxAxisY];
2829 }
2830 if (axis.valueWindow) {
2831 // This is only set if the user has zoomed on the y-axis. It is never set
2832 // by a user. It takes precedence over axis.valueRange because, if you set
2833 // valueRange, you'd still expect to be able to pan.
2834 axis.computedValueRange = [axis.valueWindow[0], axis.valueWindow[1]];
2835 } else if (axis.valueRange) {
2836 // This is a user-set value range for this axis.
2837 var y0 = isNullUndefinedOrNaN(axis.valueRange[0]) ? axis.extremeRange[0] : axis.valueRange[0];
2838 var y1 = isNullUndefinedOrNaN(axis.valueRange[1]) ? axis.extremeRange[1] : axis.valueRange[1];
2839 if (!ypadCompat) {
2840 if (axis.logscale) {
2841 var logpad = Math.exp(Math.log(span) * ypad);
2842 y0 *= logpad;
2843 y1 /= logpad;
2844 } else {
2845 span = y1 - y0;
2846 y0 -= span * ypad;
2847 y1 += span * ypad;
2848 }
2849 }
2850 axis.computedValueRange = [y0, y1];
2851 } else {
2852 axis.computedValueRange = axis.extremeRange;
2853 }
2854
2855
2856 if(independentTicks) {
2857 axis.independentTicks = independentTicks;
2858 var opts = this.optionsViewForAxis_('y' + (i ? '2' : ''));
2859 var ticker = opts('ticker');
2860 axis.ticks = ticker(axis.computedValueRange[0],
2861 axis.computedValueRange[1],
2862 this.height_, // TODO(danvk): should be area.height
2863 opts,
2864 this);
2865 // Define the first independent axis as primary axis.
2866 if (!p_axis) p_axis = axis;
2867 }
2868 }
2869 if (p_axis === undefined) {
2870 throw ("Configuration Error: At least one axis has to have the \"independentTicks\" option activated.");
2871 }
2872 // Add ticks. By default, all axes inherit the tick positions of the
2873 // primary axis. However, if an axis is specifically marked as having
2874 // independent ticks, then that is permissible as well.
2875 for (var i = 0; i < numAxes; i++) {
2876 var axis = this.axes_[i];
2877
2878 if (!axis.independentTicks) {
2879 var opts = this.optionsViewForAxis_('y' + (i ? '2' : ''));
2880 var ticker = opts('ticker');
2881 var p_ticks = p_axis.ticks;
2882 var p_scale = p_axis.computedValueRange[1] - p_axis.computedValueRange[0];
2883 var scale = axis.computedValueRange[1] - axis.computedValueRange[0];
2884 var tick_values = [];
2885 for (var k = 0; k < p_ticks.length; k++) {
2886 var y_frac = (p_ticks[k].v - p_axis.computedValueRange[0]) / p_scale;
2887 var y_val = axis.computedValueRange[0] + y_frac * scale;
2888 tick_values.push(y_val);
2889 }
2890
2891 axis.ticks = ticker(axis.computedValueRange[0],
2892 axis.computedValueRange[1],
2893 this.height_, // TODO(danvk): should be area.height
2894 opts,
2895 this,
2896 tick_values);
2897 }
2898 }
2899 };
2900
2901 /**
2902 * Extracts one series from the raw data (a 2D array) into an array of (date,
2903 * value) tuples.
2904 *
2905 * This is where undesirable points (i.e. negative values on log scales and
2906 * missing values through which we wish to connect lines) are dropped.
2907 * TODO(danvk): the "missing values" bit above doesn't seem right.
2908 *
2909 * @private
2910 * @param {Array.<Array.<(number|Array<Number>)>>} rawData Input data. Rectangular
2911 * grid of points, where rawData[row][0] is the X value for the row,
2912 * and rawData[row][i] is the Y data for series #i.
2913 * @param {number} i Series index, starting from 1.
2914 * @param {boolean} logScale True if using logarithmic Y scale.
2915 * @return {Array.<Array.<(?number|Array<?number>)>} Series array, where
2916 * series[row] = [x,y] or [x, [y, err]] or [x, [y, yplus, yminus]].
2917 */
2918 Dygraph.prototype.extractSeries_ = function(rawData, i, logScale) {
2919 // TODO(danvk): pre-allocate series here.
2920 var series = [];
2921 var errorBars = this.attr_("errorBars");
2922 var customBars = this.attr_("customBars");
2923 for (var j = 0; j < rawData.length; j++) {
2924 var x = rawData[j][0];
2925 var point = rawData[j][i];
2926 if (logScale) {
2927 // On the log scale, points less than zero do not exist.
2928 // This will create a gap in the chart.
2929 if (errorBars || customBars) {
2930 // point.length is either 2 (errorBars) or 3 (customBars)
2931 for (var k = 0; k < point.length; k++) {
2932 if (point[k] <= 0) {
2933 point = null;
2934 break;
2935 }
2936 }
2937 } else if (point <= 0) {
2938 point = null;
2939 }
2940 }
2941 // Fix null points to fit the display type standard.
2942 if (point !== null) {
2943 series.push([x, point]);
2944 } else {
2945 series.push([x, errorBars ? [null, null] : customBars ? [null, null, null] : point]);
2946 }
2947 }
2948 return series;
2949 };
2950
2951 /**
2952 * @private
2953 * Calculates the rolling average of a data set.
2954 * If originalData is [label, val], rolls the average of those.
2955 * If originalData is [label, [, it's interpreted as [value, stddev]
2956 * and the roll is returned in the same form, with appropriately reduced
2957 * stddev for each value.
2958 * Note that this is where fractional input (i.e. '5/10') is converted into
2959 * decimal values.
2960 * @param {Array} originalData The data in the appropriate format (see above)
2961 * @param {Number} rollPeriod The number of points over which to average the
2962 * data
2963 */
2964 Dygraph.prototype.rollingAverage = function(originalData, rollPeriod) {
2965 rollPeriod = Math.min(rollPeriod, originalData.length);
2966 var rollingData = [];
2967 var sigma = this.attr_("sigma");
2968
2969 var low, high, i, j, y, sum, num_ok, stddev;
2970 if (this.fractions_) {
2971 var num = 0;
2972 var den = 0; // numerator/denominator
2973 var mult = 100.0;
2974 for (i = 0; i < originalData.length; i++) {
2975 num += originalData[i][1][0];
2976 den += originalData[i][1][1];
2977 if (i - rollPeriod >= 0) {
2978 num -= originalData[i - rollPeriod][1][0];
2979 den -= originalData[i - rollPeriod][1][1];
2980 }
2981
2982 var date = originalData[i][0];
2983 var value = den ? num / den : 0.0;
2984 if (this.attr_("errorBars")) {
2985 if (this.attr_("wilsonInterval")) {
2986 // For more details on this confidence interval, see:
2987 // http://en.wikipedia.org/wiki/Binomial_confidence_interval
2988 if (den) {
2989 var p = value < 0 ? 0 : value, n = den;
2990 var pm = sigma * Math.sqrt(p*(1-p)/n + sigma*sigma/(4*n*n));
2991 var denom = 1 + sigma * sigma / den;
2992 low = (p + sigma * sigma / (2 * den) - pm) / denom;
2993 high = (p + sigma * sigma / (2 * den) + pm) / denom;
2994 rollingData[i] = [date,
2995 [p * mult, (p - low) * mult, (high - p) * mult]];
2996 } else {
2997 rollingData[i] = [date, [0, 0, 0]];
2998 }
2999 } else {
3000 stddev = den ? sigma * Math.sqrt(value * (1 - value) / den) : 1.0;
3001 rollingData[i] = [date, [mult * value, mult * stddev, mult * stddev]];
3002 }
3003 } else {
3004 rollingData[i] = [date, mult * value];
3005 }
3006 }
3007 } else if (this.attr_("customBars")) {
3008 low = 0;
3009 var mid = 0;
3010 high = 0;
3011 var count = 0;
3012 for (i = 0; i < originalData.length; i++) {
3013 var data = originalData[i][1];
3014 y = data[1];
3015 rollingData[i] = [originalData[i][0], [y, y - data[0], data[2] - y]];
3016
3017 if (y !== null && !isNaN(y)) {
3018 low += data[0];
3019 mid += y;
3020 high += data[2];
3021 count += 1;
3022 }
3023 if (i - rollPeriod >= 0) {
3024 var prev = originalData[i - rollPeriod];
3025 if (prev[1][1] !== null && !isNaN(prev[1][1])) {
3026 low -= prev[1][0];
3027 mid -= prev[1][1];
3028 high -= prev[1][2];
3029 count -= 1;
3030 }
3031 }
3032 if (count) {
3033 rollingData[i] = [originalData[i][0], [ 1.0 * mid / count,
3034 1.0 * (mid - low) / count,
3035 1.0 * (high - mid) / count ]];
3036 } else {
3037 rollingData[i] = [originalData[i][0], [null, null, null]];
3038 }
3039 }
3040 } else {
3041 // Calculate the rolling average for the first rollPeriod - 1 points where
3042 // there is not enough data to roll over the full number of points
3043 if (!this.attr_("errorBars")){
3044 if (rollPeriod == 1) {
3045 return originalData;
3046 }
3047
3048 for (i = 0; i < originalData.length; i++) {
3049 sum = 0;
3050 num_ok = 0;
3051 for (j = Math.max(0, i - rollPeriod + 1); j < i + 1; j++) {
3052 y = originalData[j][1];
3053 if (y === null || isNaN(y)) continue;
3054 num_ok++;
3055 sum += originalData[j][1];
3056 }
3057 if (num_ok) {
3058 rollingData[i] = [originalData[i][0], sum / num_ok];
3059 } else {
3060 rollingData[i] = [originalData[i][0], null];
3061 }
3062 }
3063
3064 } else {
3065 for (i = 0; i < originalData.length; i++) {
3066 sum = 0;
3067 var variance = 0;
3068 num_ok = 0;
3069 for (j = Math.max(0, i - rollPeriod + 1); j < i + 1; j++) {
3070 y = originalData[j][1][0];
3071 if (y === null || isNaN(y)) continue;
3072 num_ok++;
3073 sum += originalData[j][1][0];
3074 variance += Math.pow(originalData[j][1][1], 2);
3075 }
3076 if (num_ok) {
3077 stddev = Math.sqrt(variance) / num_ok;
3078 rollingData[i] = [originalData[i][0],
3079 [sum / num_ok, sigma * stddev, sigma * stddev]];
3080 } else {
3081 // This explicitly preserves NaNs to aid with "independent series".
3082 // See testRollingAveragePreservesNaNs.
3083 var v = (rollPeriod == 1) ? originalData[i][1][0] : null;
3084 rollingData[i] = [originalData[i][0], [v, v, v]];
3085 }
3086 }
3087 }
3088 }
3089
3090 return rollingData;
3091 };
3092
3093 /**
3094 * Detects the type of the str (date or numeric) and sets the various
3095 * formatting attributes in this.attrs_ based on this type.
3096 * @param {String} str An x value.
3097 * @private
3098 */
3099 Dygraph.prototype.detectTypeFromString_ = function(str) {
3100 var isDate = false;
3101 var dashPos = str.indexOf('-'); // could be 2006-01-01 _or_ 1.0e-2
3102 if ((dashPos > 0 && (str[dashPos-1] != 'e' && str[dashPos-1] != 'E')) ||
3103 str.indexOf('/') >= 0 ||
3104 isNaN(parseFloat(str))) {
3105 isDate = true;
3106 } else if (str.length == 8 && str > '19700101' && str < '20371231') {
3107 // TODO(danvk): remove support for this format.
3108 isDate = true;
3109 }
3110
3111 this.setXAxisOptions_(isDate);
3112 };
3113
3114 Dygraph.prototype.setXAxisOptions_ = function(isDate) {
3115 if (isDate) {
3116 this.attrs_.xValueParser = Dygraph.dateParser;
3117 this.attrs_.axes.x.valueFormatter = Dygraph.dateString_;
3118 this.attrs_.axes.x.ticker = Dygraph.dateTicker;
3119 this.attrs_.axes.x.axisLabelFormatter = Dygraph.dateAxisFormatter;
3120 } else {
3121 /** @private (shut up, jsdoc!) */
3122 this.attrs_.xValueParser = function(x) { return parseFloat(x); };
3123 // TODO(danvk): use Dygraph.numberValueFormatter here?
3124 /** @private (shut up, jsdoc!) */
3125 this.attrs_.axes.x.valueFormatter = function(x) { return x; };
3126 this.attrs_.axes.x.ticker = Dygraph.numericLinearTicks;
3127 this.attrs_.axes.x.axisLabelFormatter = this.attrs_.axes.x.valueFormatter;
3128 }
3129 };
3130
3131 /**
3132 * Parses the value as a floating point number. This is like the parseFloat()
3133 * built-in, but with a few differences:
3134 * - the empty string is parsed as null, rather than NaN.
3135 * - if the string cannot be parsed at all, an error is logged.
3136 * If the string can't be parsed, this method returns null.
3137 * @param {String} x The string to be parsed
3138 * @param {Number} opt_line_no The line number from which the string comes.
3139 * @param {String} opt_line The text of the line from which the string comes.
3140 * @private
3141 */
3142
3143 // Parse the x as a float or return null if it's not a number.
3144 Dygraph.prototype.parseFloat_ = function(x, opt_line_no, opt_line) {
3145 var val = parseFloat(x);
3146 if (!isNaN(val)) return val;
3147
3148 // Try to figure out what happeend.
3149 // If the value is the empty string, parse it as null.
3150 if (/^ *$/.test(x)) return null;
3151
3152 // If it was actually "NaN", return it as NaN.
3153 if (/^ *nan *$/i.test(x)) return NaN;
3154
3155 // Looks like a parsing error.
3156 var msg = "Unable to parse '" + x + "' as a number";
3157 if (opt_line !== null && opt_line_no !== null) {
3158 msg += " on line " + (1+opt_line_no) + " ('" + opt_line + "') of CSV.";
3159 }
3160 this.error(msg);
3161
3162 return null;
3163 };
3164
3165 /**
3166 * @private
3167 * Parses a string in a special csv format. We expect a csv file where each
3168 * line is a date point, and the first field in each line is the date string.
3169 * We also expect that all remaining fields represent series.
3170 * if the errorBars attribute is set, then interpret the fields as:
3171 * date, series1, stddev1, series2, stddev2, ...
3172 * @param {[Object]} data See above.
3173 *
3174 * @return [Object] An array with one entry for each row. These entries
3175 * are an array of cells in that row. The first entry is the parsed x-value for
3176 * the row. The second, third, etc. are the y-values. These can take on one of
3177 * three forms, depending on the CSV and constructor parameters:
3178 * 1. numeric value
3179 * 2. [ value, stddev ]
3180 * 3. [ low value, center value, high value ]
3181 */
3182 Dygraph.prototype.parseCSV_ = function(data) {
3183 var ret = [];
3184 var line_delimiter = Dygraph.detectLineDelimiter(data);
3185 var lines = data.split(line_delimiter || "\n");
3186 var vals, j;
3187
3188 // Use the default delimiter or fall back to a tab if that makes sense.
3189 var delim = this.attr_('delimiter');
3190 if (lines[0].indexOf(delim) == -1 && lines[0].indexOf('\t') >= 0) {
3191 delim = '\t';
3192 }
3193
3194 var start = 0;
3195 if (!('labels' in this.user_attrs_)) {
3196 // User hasn't explicitly set labels, so they're (presumably) in the CSV.
3197 start = 1;
3198 this.attrs_.labels = lines[0].split(delim); // NOTE: _not_ user_attrs_.
3199 this.attributes_.reparseSeries();
3200 }
3201 var line_no = 0;
3202
3203 var xParser;
3204 var defaultParserSet = false; // attempt to auto-detect x value type
3205 var expectedCols = this.attr_("labels").length;
3206 var outOfOrder = false;
3207 for (var i = start; i < lines.length; i++) {
3208 var line = lines[i];
3209 line_no = i;
3210 if (line.length === 0) continue; // skip blank lines
3211 if (line[0] == '#') continue; // skip comment lines
3212 var inFields = line.split(delim);
3213 if (inFields.length < 2) continue;
3214
3215 var fields = [];
3216 if (!defaultParserSet) {
3217 this.detectTypeFromString_(inFields[0]);
3218 xParser = this.attr_("xValueParser");
3219 defaultParserSet = true;
3220 }
3221 fields[0] = xParser(inFields[0], this);
3222
3223 // If fractions are expected, parse the numbers as "A/B"
3224 if (this.fractions_) {
3225 for (j = 1; j < inFields.length; j++) {
3226 // TODO(danvk): figure out an appropriate way to flag parse errors.
3227 vals = inFields[j].split("/");
3228 if (vals.length != 2) {
3229 this.error('Expected fractional "num/den" values in CSV data ' +
3230 "but found a value '" + inFields[j] + "' on line " +
3231 (1 + i) + " ('" + line + "') which is not of this form.");
3232 fields[j] = [0, 0];
3233 } else {
3234 fields[j] = [this.parseFloat_(vals[0], i, line),
3235 this.parseFloat_(vals[1], i, line)];
3236 }
3237 }
3238 } else if (this.attr_("errorBars")) {
3239 // If there are error bars, values are (value, stddev) pairs
3240 if (inFields.length % 2 != 1) {
3241 this.error('Expected alternating (value, stdev.) pairs in CSV data ' +
3242 'but line ' + (1 + i) + ' has an odd number of values (' +
3243 (inFields.length - 1) + "): '" + line + "'");
3244 }
3245 for (j = 1; j < inFields.length; j += 2) {
3246 fields[(j + 1) / 2] = [this.parseFloat_(inFields[j], i, line),
3247 this.parseFloat_(inFields[j + 1], i, line)];
3248 }
3249 } else if (this.attr_("customBars")) {
3250 // Bars are a low;center;high tuple
3251 for (j = 1; j < inFields.length; j++) {
3252 var val = inFields[j];
3253 if (/^ *$/.test(val)) {
3254 fields[j] = [null, null, null];
3255 } else {
3256 vals = val.split(";");
3257 if (vals.length == 3) {
3258 fields[j] = [ this.parseFloat_(vals[0], i, line),
3259 this.parseFloat_(vals[1], i, line),
3260 this.parseFloat_(vals[2], i, line) ];
3261 } else {
3262 this.warn('When using customBars, values must be either blank ' +
3263 'or "low;center;high" tuples (got "' + val +
3264 '" on line ' + (1+i));
3265 }
3266 }
3267 }
3268 } else {
3269 // Values are just numbers
3270 for (j = 1; j < inFields.length; j++) {
3271 fields[j] = this.parseFloat_(inFields[j], i, line);
3272 }
3273 }
3274 if (ret.length > 0 && fields[0] < ret[ret.length - 1][0]) {
3275 outOfOrder = true;
3276 }
3277
3278 if (fields.length != expectedCols) {
3279 this.error("Number of columns in line " + i + " (" + fields.length +
3280 ") does not agree with number of labels (" + expectedCols +
3281 ") " + line);
3282 }
3283
3284 // If the user specified the 'labels' option and none of the cells of the
3285 // first row parsed correctly, then they probably double-specified the
3286 // labels. We go with the values set in the option, discard this row and
3287 // log a warning to the JS console.
3288 if (i === 0 && this.attr_('labels')) {
3289 var all_null = true;
3290 for (j = 0; all_null && j < fields.length; j++) {
3291 if (fields[j]) all_null = false;
3292 }
3293 if (all_null) {
3294 this.warn("The dygraphs 'labels' option is set, but the first row of " +
3295 "CSV data ('" + line + "') appears to also contain labels. " +
3296 "Will drop the CSV labels and use the option labels.");
3297 continue;
3298 }
3299 }
3300 ret.push(fields);
3301 }
3302
3303 if (outOfOrder) {
3304 this.warn("CSV is out of order; order it correctly to speed loading.");
3305 ret.sort(function(a,b) { return a[0] - b[0]; });
3306 }
3307
3308 return ret;
3309 };
3310
3311 /**
3312 * @private
3313 * The user has provided their data as a pre-packaged JS array. If the x values
3314 * are numeric, this is the same as dygraphs' internal format. If the x values
3315 * are dates, we need to convert them from Date objects to ms since epoch.
3316 * @param {[Object]} data
3317 * @return {[Object]} data with numeric x values.
3318 */
3319 Dygraph.prototype.parseArray_ = function(data) {
3320 // Peek at the first x value to see if it's numeric.
3321 if (data.length === 0) {
3322 this.error("Can't plot empty data set");
3323 return null;
3324 }
3325 if (data[0].length === 0) {
3326 this.error("Data set cannot contain an empty row");
3327 return null;
3328 }
3329
3330 var i;
3331 if (this.attr_("labels") === null) {
3332 this.warn("Using default labels. Set labels explicitly via 'labels' " +
3333 "in the options parameter");
3334 this.attrs_.labels = [ "X" ];
3335 for (i = 1; i < data[0].length; i++) {
3336 this.attrs_.labels.push("Y" + i); // Not user_attrs_.
3337 }
3338 this.attributes_.reparseSeries();
3339 } else {
3340 var num_labels = this.attr_("labels");
3341 if (num_labels.length != data[0].length) {
3342 this.error("Mismatch between number of labels (" + num_labels +
3343 ") and number of columns in array (" + data[0].length + ")");
3344 return null;
3345 }
3346 }
3347
3348 if (Dygraph.isDateLike(data[0][0])) {
3349 // Some intelligent defaults for a date x-axis.
3350 this.attrs_.axes.x.valueFormatter = Dygraph.dateString_;
3351 this.attrs_.axes.x.ticker = Dygraph.dateTicker;
3352 this.attrs_.axes.x.axisLabelFormatter = Dygraph.dateAxisFormatter;
3353
3354 // Assume they're all dates.
3355 var parsedData = Dygraph.clone(data);
3356 for (i = 0; i < data.length; i++) {
3357 if (parsedData[i].length === 0) {
3358 this.error("Row " + (1 + i) + " of data is empty");
3359 return null;
3360 }
3361 if (parsedData[i][0] === null ||
3362 typeof(parsedData[i][0].getTime) != 'function' ||
3363 isNaN(parsedData[i][0].getTime())) {
3364 this.error("x value in row " + (1 + i) + " is not a Date");
3365 return null;
3366 }
3367 parsedData[i][0] = parsedData[i][0].getTime();
3368 }
3369 return parsedData;
3370 } else {
3371 // Some intelligent defaults for a numeric x-axis.
3372 /** @private (shut up, jsdoc!) */
3373 this.attrs_.axes.x.valueFormatter = function(x) { return x; };
3374 this.attrs_.axes.x.ticker = Dygraph.numericLinearTicks;
3375 this.attrs_.axes.x.axisLabelFormatter = Dygraph.numberAxisLabelFormatter;
3376 return data;
3377 }
3378 };
3379
3380 /**
3381 * Parses a DataTable object from gviz.
3382 * The data is expected to have a first column that is either a date or a
3383 * number. All subsequent columns must be numbers. If there is a clear mismatch
3384 * between this.xValueParser_ and the type of the first column, it will be
3385 * fixed. Fills out rawData_.
3386 * @param {[Object]} data See above.
3387 * @private
3388 */
3389 Dygraph.prototype.parseDataTable_ = function(data) {
3390 var shortTextForAnnotationNum = function(num) {
3391 // converts [0-9]+ [A-Z][a-z]*
3392 // example: 0=A, 1=B, 25=Z, 26=Aa, 27=Ab
3393 // and continues like.. Ba Bb .. Za .. Zz..Aaa...Zzz Aaaa Zzzz
3394 var shortText = String.fromCharCode(65 /* A */ + num % 26);
3395 num = Math.floor(num / 26);
3396 while ( num > 0 ) {
3397 shortText = String.fromCharCode(65 /* A */ + (num - 1) % 26 ) + shortText.toLowerCase();
3398 num = Math.floor((num - 1) / 26);
3399 }
3400 return shortText;
3401 };
3402
3403 var cols = data.getNumberOfColumns();
3404 var rows = data.getNumberOfRows();
3405
3406 var indepType = data.getColumnType(0);
3407 if (indepType == 'date' || indepType == 'datetime') {
3408 this.attrs_.xValueParser = Dygraph.dateParser;
3409 this.attrs_.axes.x.valueFormatter = Dygraph.dateString_;
3410 this.attrs_.axes.x.ticker = Dygraph.dateTicker;
3411 this.attrs_.axes.x.axisLabelFormatter = Dygraph.dateAxisFormatter;
3412 } else if (indepType == 'number') {
3413 this.attrs_.xValueParser = function(x) { return parseFloat(x); };
3414 this.attrs_.axes.x.valueFormatter = function(x) { return x; };
3415 this.attrs_.axes.x.ticker = Dygraph.numericLinearTicks;
3416 this.attrs_.axes.x.axisLabelFormatter = this.attrs_.axes.x.valueFormatter;
3417 } else {
3418 this.error("only 'date', 'datetime' and 'number' types are supported for " +
3419 "column 1 of DataTable input (Got '" + indepType + "')");
3420 return null;
3421 }
3422
3423 // Array of the column indices which contain data (and not annotations).
3424 var colIdx = [];
3425 var annotationCols = {}; // data index -> [annotation cols]
3426 var hasAnnotations = false;
3427 var i, j;
3428 for (i = 1; i < cols; i++) {
3429 var type = data.getColumnType(i);
3430 if (type == 'number') {
3431 colIdx.push(i);
3432 } else if (type == 'string' && this.attr_('displayAnnotations')) {
3433 // This is OK -- it's an annotation column.
3434 var dataIdx = colIdx[colIdx.length - 1];
3435 if (!annotationCols.hasOwnProperty(dataIdx)) {
3436 annotationCols[dataIdx] = [i];
3437 } else {
3438 annotationCols[dataIdx].push(i);
3439 }
3440 hasAnnotations = true;
3441 } else {
3442 this.error("Only 'number' is supported as a dependent type with Gviz." +
3443 " 'string' is only supported if displayAnnotations is true");
3444 }
3445 }
3446
3447 // Read column labels
3448 // TODO(danvk): add support back for errorBars
3449 var labels = [data.getColumnLabel(0)];
3450 for (i = 0; i < colIdx.length; i++) {
3451 labels.push(data.getColumnLabel(colIdx[i]));
3452 if (this.attr_("errorBars")) i += 1;
3453 }
3454 this.attrs_.labels = labels;
3455 cols = labels.length;
3456
3457 var ret = [];
3458 var outOfOrder = false;
3459 var annotations = [];
3460 for (i = 0; i < rows; i++) {
3461 var row = [];
3462 if (typeof(data.getValue(i, 0)) === 'undefined' ||
3463 data.getValue(i, 0) === null) {
3464 this.warn("Ignoring row " + i +
3465 " of DataTable because of undefined or null first column.");
3466 continue;
3467 }
3468
3469 if (indepType == 'date' || indepType == 'datetime') {
3470 row.push(data.getValue(i, 0).getTime());
3471 } else {
3472 row.push(data.getValue(i, 0));
3473 }
3474 if (!this.attr_("errorBars")) {
3475 for (j = 0; j < colIdx.length; j++) {
3476 var col = colIdx[j];
3477 row.push(data.getValue(i, col));
3478 if (hasAnnotations &&
3479 annotationCols.hasOwnProperty(col) &&
3480 data.getValue(i, annotationCols[col][0]) !== null) {
3481 var ann = {};
3482 ann.series = data.getColumnLabel(col);
3483 ann.xval = row[0];
3484 ann.shortText = shortTextForAnnotationNum(annotations.length);
3485 ann.text = '';
3486 for (var k = 0; k < annotationCols[col].length; k++) {
3487 if (k) ann.text += "\n";
3488 ann.text += data.getValue(i, annotationCols[col][k]);
3489 }
3490 annotations.push(ann);
3491 }
3492 }
3493
3494 // Strip out infinities, which give dygraphs problems later on.
3495 for (j = 0; j < row.length; j++) {
3496 if (!isFinite(row[j])) row[j] = null;
3497 }
3498 } else {
3499 for (j = 0; j < cols - 1; j++) {
3500 row.push([ data.getValue(i, 1 + 2 * j), data.getValue(i, 2 + 2 * j) ]);
3501 }
3502 }
3503 if (ret.length > 0 && row[0] < ret[ret.length - 1][0]) {
3504 outOfOrder = true;
3505 }
3506 ret.push(row);
3507 }
3508
3509 if (outOfOrder) {
3510 this.warn("DataTable is out of order; order it correctly to speed loading.");
3511 ret.sort(function(a,b) { return a[0] - b[0]; });
3512 }
3513 this.rawData_ = ret;
3514
3515 if (annotations.length > 0) {
3516 this.setAnnotations(annotations, true);
3517 }
3518 this.attributes_.reparseSeries();
3519 };
3520
3521 /**
3522 * Get the CSV data. If it's in a function, call that function. If it's in a
3523 * file, do an XMLHttpRequest to get it.
3524 * @private
3525 */
3526 Dygraph.prototype.start_ = function() {
3527 var data = this.file_;
3528
3529 // Functions can return references of all other types.
3530 if (typeof data == 'function') {
3531 data = data();
3532 }
3533
3534 if (Dygraph.isArrayLike(data)) {
3535 this.rawData_ = this.parseArray_(data);
3536 this.predraw_();
3537 } else if (typeof data == 'object' &&
3538 typeof data.getColumnRange == 'function') {
3539 // must be a DataTable from gviz.
3540 this.parseDataTable_(data);
3541 this.predraw_();
3542 } else if (typeof data == 'string') {
3543 // Heuristic: a newline means it's CSV data. Otherwise it's an URL.
3544 var line_delimiter = Dygraph.detectLineDelimiter(data);
3545 if (line_delimiter) {
3546 this.loadedEvent_(data);
3547 } else {
3548 var req = new XMLHttpRequest();
3549 var caller = this;
3550 req.onreadystatechange = function () {
3551 if (req.readyState == 4) {
3552 if (req.status === 200 || // Normal http
3553 req.status === 0) { // Chrome w/ --allow-file-access-from-files
3554 caller.loadedEvent_(req.responseText);
3555 }
3556 }
3557 };
3558
3559 req.open("GET", data, true);
3560 req.send(null);
3561 }
3562 } else {
3563 this.error("Unknown data format: " + (typeof data));
3564 }
3565 };
3566
3567 /**
3568 * Changes various properties of the graph. These can include:
3569 * <ul>
3570 * <li>file: changes the source data for the graph</li>
3571 * <li>errorBars: changes whether the data contains stddev</li>
3572 * </ul>
3573 *
3574 * There's a huge variety of options that can be passed to this method. For a
3575 * full list, see http://dygraphs.com/options.html.
3576 *
3577 * @param {Object} attrs The new properties and values
3578 * @param {Boolean} [block_redraw] Usually the chart is redrawn after every
3579 * call to updateOptions(). If you know better, you can pass true to explicitly
3580 * block the redraw. This can be useful for chaining updateOptions() calls,
3581 * avoiding the occasional infinite loop and preventing redraws when it's not
3582 * necessary (e.g. when updating a callback).
3583 */
3584 Dygraph.prototype.updateOptions = function(input_attrs, block_redraw) {
3585 if (typeof(block_redraw) == 'undefined') block_redraw = false;
3586
3587 // mapLegacyOptions_ drops the "file" parameter as a convenience to us.
3588 var file = input_attrs.file;
3589 var attrs = Dygraph.mapLegacyOptions_(input_attrs);
3590
3591 // TODO(danvk): this is a mess. Move these options into attr_.
3592 if ('rollPeriod' in attrs) {
3593 this.rollPeriod_ = attrs.rollPeriod;
3594 }
3595 if ('dateWindow' in attrs) {
3596 this.dateWindow_ = attrs.dateWindow;
3597 if (!('isZoomedIgnoreProgrammaticZoom' in attrs)) {
3598 this.zoomed_x_ = (attrs.dateWindow !== null);
3599 }
3600 }
3601 if ('valueRange' in attrs && !('isZoomedIgnoreProgrammaticZoom' in attrs)) {
3602 this.zoomed_y_ = (attrs.valueRange !== null);
3603 }
3604
3605 // TODO(danvk): validate per-series options.
3606 // Supported:
3607 // strokeWidth
3608 // pointSize
3609 // drawPoints
3610 // highlightCircleSize
3611
3612 // Check if this set options will require new points.
3613 var requiresNewPoints = Dygraph.isPixelChangingOptionList(this.attr_("labels"), attrs);
3614
3615 Dygraph.updateDeep(this.user_attrs_, attrs);
3616
3617 this.attributes_.reparseSeries();
3618
3619 if (file) {
3620 this.file_ = file;
3621 if (!block_redraw) this.start_();
3622 } else {
3623 if (!block_redraw) {
3624 if (requiresNewPoints) {
3625 this.predraw_();
3626 } else {
3627 this.renderGraph_(false);
3628 }
3629 }
3630 }
3631 };
3632
3633 /**
3634 * Returns a copy of the options with deprecated names converted into current
3635 * names. Also drops the (potentially-large) 'file' attribute. If the caller is
3636 * interested in that, they should save a copy before calling this.
3637 * @private
3638 */
3639 Dygraph.mapLegacyOptions_ = function(attrs) {
3640 var my_attrs = {};
3641 for (var k in attrs) {
3642 if (k == 'file') continue;
3643 if (attrs.hasOwnProperty(k)) my_attrs[k] = attrs[k];
3644 }
3645
3646 var set = function(axis, opt, value) {
3647 if (!my_attrs.axes) my_attrs.axes = {};
3648 if (!my_attrs.axes[axis]) my_attrs.axes[axis] = {};
3649 my_attrs.axes[axis][opt] = value;
3650 };
3651 var map = function(opt, axis, new_opt) {
3652 if (typeof(attrs[opt]) != 'undefined') {
3653 Dygraph.warn("Option " + opt + " is deprecated. Use the " +
3654 new_opt + " option for the " + axis + " axis instead. " +
3655 "(e.g. { axes : { " + axis + " : { " + new_opt + " : ... } } } " +
3656 "(see http://dygraphs.com/per-axis.html for more information.");
3657 set(axis, new_opt, attrs[opt]);
3658 delete my_attrs[opt];
3659 }
3660 };
3661
3662 // This maps, e.g., xValueFormater -> axes: { x: { valueFormatter: ... } }
3663 map('xValueFormatter', 'x', 'valueFormatter');
3664 map('pixelsPerXLabel', 'x', 'pixelsPerLabel');
3665 map('xAxisLabelFormatter', 'x', 'axisLabelFormatter');
3666 map('xTicker', 'x', 'ticker');
3667 map('yValueFormatter', 'y', 'valueFormatter');
3668 map('pixelsPerYLabel', 'y', 'pixelsPerLabel');
3669 map('yAxisLabelFormatter', 'y', 'axisLabelFormatter');
3670 map('yTicker', 'y', 'ticker');
3671 return my_attrs;
3672 };
3673
3674 /**
3675 * Resizes the dygraph. If no parameters are specified, resizes to fill the
3676 * containing div (which has presumably changed size since the dygraph was
3677 * instantiated. If the width/height are specified, the div will be resized.
3678 *
3679 * This is far more efficient than destroying and re-instantiating a
3680 * Dygraph, since it doesn't have to reparse the underlying data.
3681 *
3682 * @param {Number} [width] Width (in pixels)
3683 * @param {Number} [height] Height (in pixels)
3684 */
3685 Dygraph.prototype.resize = function(width, height) {
3686 if (this.resize_lock) {
3687 return;
3688 }
3689 this.resize_lock = true;
3690
3691 if ((width === null) != (height === null)) {
3692 this.warn("Dygraph.resize() should be called with zero parameters or " +
3693 "two non-NULL parameters. Pretending it was zero.");
3694 width = height = null;
3695 }
3696
3697 var old_width = this.width_;
3698 var old_height = this.height_;
3699
3700 if (width) {
3701 this.maindiv_.style.width = width + "px";
3702 this.maindiv_.style.height = height + "px";
3703 this.width_ = width;
3704 this.height_ = height;
3705 } else {
3706 this.width_ = this.maindiv_.clientWidth;
3707 this.height_ = this.maindiv_.clientHeight;
3708 }
3709
3710 if (old_width != this.width_ || old_height != this.height_) {
3711 // Resizing a canvas erases it, even when the size doesn't change, so
3712 // any resize needs to be followed by a redraw.
3713 this.resizeElements_();
3714 this.predraw_();
3715 }
3716
3717 this.resize_lock = false;
3718 };
3719
3720 /**
3721 * Adjusts the number of points in the rolling average. Updates the graph to
3722 * reflect the new averaging period.
3723 * @param {Number} length Number of points over which to average the data.
3724 */
3725 Dygraph.prototype.adjustRoll = function(length) {
3726 this.rollPeriod_ = length;
3727 this.predraw_();
3728 };
3729
3730 /**
3731 * Returns a boolean array of visibility statuses.
3732 */
3733 Dygraph.prototype.visibility = function() {
3734 // Do lazy-initialization, so that this happens after we know the number of
3735 // data series.
3736 if (!this.attr_("visibility")) {
3737 this.attrs_.visibility = [];
3738 }
3739 // TODO(danvk): it looks like this could go into an infinite loop w/ user_attrs.
3740 while (this.attr_("visibility").length < this.numColumns() - 1) {
3741 this.attrs_.visibility.push(true);
3742 }
3743 return this.attr_("visibility");
3744 };
3745
3746 /**
3747 * Changes the visiblity of a series.
3748 */
3749 Dygraph.prototype.setVisibility = function(num, value) {
3750 var x = this.visibility();
3751 if (num < 0 || num >= x.length) {
3752 this.warn("invalid series number in setVisibility: " + num);
3753 } else {
3754 x[num] = value;
3755 this.predraw_();
3756 }
3757 };
3758
3759 /**
3760 * How large of an area will the dygraph render itself in?
3761 * This is used for testing.
3762 * @return A {width: w, height: h} object.
3763 * @private
3764 */
3765 Dygraph.prototype.size = function() {
3766 return { width: this.width_, height: this.height_ };
3767 };
3768
3769 /**
3770 * Update the list of annotations and redraw the chart.
3771 * See dygraphs.com/annotations.html for more info on how to use annotations.
3772 * @param ann {Array} An array of annotation objects.
3773 * @param suppressDraw {Boolean} Set to "true" to block chart redraw (optional).
3774 */
3775 Dygraph.prototype.setAnnotations = function(ann, suppressDraw) {
3776 // Only add the annotation CSS rule once we know it will be used.
3777 Dygraph.addAnnotationRule();
3778 this.annotations_ = ann;
3779 if (!this.layout_) {
3780 this.warn("Tried to setAnnotations before dygraph was ready. " +
3781 "Try setting them in a drawCallback. See " +
3782 "dygraphs.com/tests/annotation.html");
3783 return;
3784 }
3785
3786 this.layout_.setAnnotations(this.annotations_);
3787 if (!suppressDraw) {
3788 this.predraw_();
3789 }
3790 };
3791
3792 /**
3793 * Return the list of annotations.
3794 */
3795 Dygraph.prototype.annotations = function() {
3796 return this.annotations_;
3797 };
3798
3799 /**
3800 * Get the list of label names for this graph. The first column is the
3801 * x-axis, so the data series names start at index 1.
3802 *
3803 * Returns null when labels have not yet been defined.
3804 */
3805 Dygraph.prototype.getLabels = function() {
3806 var labels = this.attr_("labels");
3807 return labels ? labels.slice() : null;
3808 };
3809
3810 /**
3811 * Get the index of a series (column) given its name. The first column is the
3812 * x-axis, so the data series start with index 1.
3813 */
3814 Dygraph.prototype.indexFromSetName = function(name) {
3815 return this.setIndexByName_[name];
3816 };
3817
3818 /**
3819 * Get the internal dataset index given its name. These are numbered starting from 0,
3820 * and only count visible sets.
3821 * @private
3822 */
3823 Dygraph.prototype.datasetIndexFromSetName_ = function(name) {
3824 return this.datasetIndex_[this.indexFromSetName(name)];
3825 };
3826
3827 /**
3828 * @private
3829 * Adds a default style for the annotation CSS classes to the document. This is
3830 * only executed when annotations are actually used. It is designed to only be
3831 * called once -- all calls after the first will return immediately.
3832 */
3833 Dygraph.addAnnotationRule = function() {
3834 // TODO(danvk): move this function into plugins/annotations.js?
3835 if (Dygraph.addedAnnotationCSS) return;
3836
3837 var rule = "border: 1px solid black; " +
3838 "background-color: white; " +
3839 "text-align: center;";
3840
3841 var styleSheetElement = document.createElement("style");
3842 styleSheetElement.type = "text/css";
3843 document.getElementsByTagName("head")[0].appendChild(styleSheetElement);
3844
3845 // Find the first style sheet that we can access.
3846 // We may not add a rule to a style sheet from another domain for security
3847 // reasons. This sometimes comes up when using gviz, since the Google gviz JS
3848 // adds its own style sheets from google.com.
3849 for (var i = 0; i < document.styleSheets.length; i++) {
3850 if (document.styleSheets[i].disabled) continue;
3851 var mysheet = document.styleSheets[i];
3852 try {
3853 if (mysheet.insertRule) { // Firefox
3854 var idx = mysheet.cssRules ? mysheet.cssRules.length : 0;
3855 mysheet.insertRule(".dygraphDefaultAnnotation { " + rule + " }", idx);
3856 } else if (mysheet.addRule) { // IE
3857 mysheet.addRule(".dygraphDefaultAnnotation", rule);
3858 }
3859 Dygraph.addedAnnotationCSS = true;
3860 return;
3861 } catch(err) {
3862 // Was likely a security exception.
3863 }
3864 }
3865
3866 this.warn("Unable to add default annotation CSS rule; display may be off.");
3867 };
3868
3869 // Older pages may still use this name.
3870 var DateGraph = Dygraph;