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