Add JSHint and make dygraphs pass its checks.
[dygraphs.git] / dygraph-range-selector.js
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1// Copyright 2011 Paul Felix (paul.eric.felix@gmail.com)
2// All Rights Reserved.
3
4/**
5 * @fileoverview This file contains the DygraphRangeSelector class used to provide
6 * a timeline range selector widget for dygraphs.
7 */
8
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9/*jshint globalstrict: true */
10/*global Dygraph:false */
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11"use strict";
12
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13/**
14 * The DygraphRangeSelector class provides a timeline range selector widget.
15 * @param {Dygraph} dygraph The dygraph object
16 * @constructor
17 */
c0f54d4f 18var DygraphRangeSelector = function(dygraph) {
ccd9d7c2 19 this.isIE_ = /MSIE/.test(navigator.userAgent) && !window.opera;
920208fb 20 this.isUsingExcanvas_ = dygraph.isUsingExcanvas_;
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21 this.dygraph_ = dygraph;
22 this.createCanvases_();
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23 if (this.isUsingExcanvas_) {
24 this.createIEPanOverlay_();
25 }
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26 this.createZoomHandles_();
27 this.initInteraction_();
28};
29
30/**
31 * Adds the range selector to the dygraph.
32 * @param {Object} graphDiv The container div for the range selector.
33 * @param {DygraphLayout} layout The DygraphLayout object for this graph.
34 */
35DygraphRangeSelector.prototype.addToGraph = function(graphDiv, layout) {
36 this.layout_ = layout;
37 this.resize_();
38 graphDiv.appendChild(this.bgcanvas_);
39 graphDiv.appendChild(this.fgcanvas_);
40 graphDiv.appendChild(this.leftZoomHandle_);
41 graphDiv.appendChild(this.rightZoomHandle_);
42};
43
44/**
45 * Renders the static background portion of the range selector.
46 */
47DygraphRangeSelector.prototype.renderStaticLayer = function() {
48 this.resize_();
49 this.drawStaticLayer_();
50};
51
52/**
53 * Renders the interactive foreground portion of the range selector.
54 */
55DygraphRangeSelector.prototype.renderInteractiveLayer = function() {
56 if (this.isChangingRange_) {
57 return;
58 }
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59 this.placeZoomHandles_();
60 this.drawInteractiveLayer_();
61};
62
63/**
64 * @private
65 * Resizes the range selector.
66 */
67DygraphRangeSelector.prototype.resize_ = function() {
920208fb 68 function setElementRect(canvas, rect) {
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69 canvas.style.top = rect.y + 'px';
70 canvas.style.left = rect.x + 'px';
71 canvas.width = rect.w;
72 canvas.height = rect.h;
73 canvas.style.width = canvas.width + 'px'; // for IE
74 canvas.style.height = canvas.height + 'px'; // for IE
758a629f 75 }
ccd9d7c2 76
70be5ed1 77 var plotArea = this.layout_.getPlotArea();
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78 var xAxisLabelHeight = this.attr_('axisLabelFontSize') + 2 * this.attr_('axisTickSize');
79 this.canvasRect_ = {
80 x: plotArea.x,
81 y: plotArea.y + plotArea.h + xAxisLabelHeight + 4,
82 w: plotArea.w,
83 h: this.attr_('rangeSelectorHeight')
84 };
85
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86 setElementRect(this.bgcanvas_, this.canvasRect_);
87 setElementRect(this.fgcanvas_, this.canvasRect_);
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88};
89
90DygraphRangeSelector.prototype.attr_ = function(name) {
91 return this.dygraph_.attr_(name);
92};
93
94/**
95 * @private
96 * Creates the background and foreground canvases.
97 */
98DygraphRangeSelector.prototype.createCanvases_ = function() {
99 this.bgcanvas_ = Dygraph.createCanvas();
88c4a47e 100 this.bgcanvas_.className = 'dygraph-rangesel-bgcanvas';
ccd9d7c2 101 this.bgcanvas_.style.position = 'absolute';
920208fb 102 this.bgcanvas_.style.zIndex = 9;
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103 this.bgcanvas_ctx_ = Dygraph.getContext(this.bgcanvas_);
104
105 this.fgcanvas_ = Dygraph.createCanvas();
88c4a47e 106 this.fgcanvas_.className = 'dygraph-rangesel-fgcanvas';
ccd9d7c2 107 this.fgcanvas_.style.position = 'absolute';
920208fb 108 this.fgcanvas_.style.zIndex = 9;
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109 this.fgcanvas_.style.cursor = 'default';
110 this.fgcanvas_ctx_ = Dygraph.getContext(this.fgcanvas_);
111};
112
113/**
114 * @private
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115 * Creates overlay divs for IE/Excanvas so that mouse events are handled properly.
116 */
117DygraphRangeSelector.prototype.createIEPanOverlay_ = function() {
118 this.iePanOverlay_ = document.createElement("div");
119 this.iePanOverlay_.style.position = 'absolute';
120 this.iePanOverlay_.style.backgroundColor = 'white';
121 this.iePanOverlay_.style.filter = 'alpha(opacity=0)';
122 this.iePanOverlay_.style.display = 'none';
123 this.iePanOverlay_.style.cursor = 'move';
124 this.fgcanvas_.appendChild(this.iePanOverlay_);
125};
126
127/**
128 * @private
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129 * Creates the zoom handle elements.
130 */
131DygraphRangeSelector.prototype.createZoomHandles_ = function() {
132 var img = new Image();
88c4a47e 133 img.className = 'dygraph-rangesel-zoomhandle';
ccd9d7c2 134 img.style.position = 'absolute';
920208fb 135 img.style.zIndex = 10;
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136 img.style.visibility = 'hidden'; // Initially hidden so they don't show up in the wrong place.
137 img.style.cursor = 'col-resize';
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138 if (/MSIE 7/.test(navigator.userAgent)) { // IE7 doesn't support embedded src data.
139 img.width = 7;
140 img.height = 14;
141 img.style.backgroundColor = 'white';
142 img.style.border = '1px solid #333333'; // Just show box in IE7.
143 } else {
144 img.width = 9;
145 img.height = 16;
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146 img.src = 'data:image/png;base64,' +
147'iVBORw0KGgoAAAANSUhEUgAAAAkAAAAQCAYAAADESFVDAAAAAXNSR0IArs4c6QAAAAZiS0dEANAA' +
148'zwDP4Z7KegAAAAlwSFlzAAAOxAAADsQBlSsOGwAAAAd0SU1FB9sHGw0cMqdt1UwAAAAZdEVYdENv' +
149'bW1lbnQAQ3JlYXRlZCB3aXRoIEdJTVBXgQ4XAAAAaElEQVQoz+3SsRFAQBCF4Z9WJM8KCDVwownl' +
150'6YXsTmCUsyKGkZzcl7zkz3YLkypgAnreFmDEpHkIwVOMfpdi9CEEN2nGpFdwD03yEqDtOgCaun7s' +
151'qSTDH32I1pQA2Pb9sZecAxc5r3IAb21d6878xsAAAAAASUVORK5CYII=';
920208fb 152 }
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153
154 this.leftZoomHandle_ = img;
155 this.rightZoomHandle_ = img.cloneNode(false);
156};
157
158/**
159 * @private
160 * Sets up the interaction for the range selector.
161 */
162DygraphRangeSelector.prototype.initInteraction_ = function() {
163 var self = this;
164 var topElem = this.isIE_ ? document : window;
165 var xLast = 0;
166 var handle = null;
167 var isZooming = false;
168 var isPanning = false;
169
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170 // functions, defined below. Defining them this way (rather than with
171 // "function foo() {...}" makes JSHint happy.
172 var toXDataWindow, onZoomStart, onZoom, onZoomEnd, doZoom, isMouseInPanZone,
173 onPanStart, onPan, onPanEnd, doPan, onCanvasMouseMove;
174
175 toXDataWindow = function(zoomHandleStatus) {
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176 var xDataLimits = self.dygraph_.xAxisExtremes();
177 var fact = (xDataLimits[1] - xDataLimits[0])/self.canvasRect_.w;
178 var xDataMin = xDataLimits[0] + (zoomHandleStatus.leftHandlePos - self.canvasRect_.x)*fact;
179 var xDataMax = xDataLimits[0] + (zoomHandleStatus.rightHandlePos - self.canvasRect_.x)*fact;
180 return [xDataMin, xDataMax];
181 };
182
758a629f 183 onZoomStart = function(e) {
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184 Dygraph.cancelEvent(e);
185 isZooming = true;
186 xLast = e.screenX;
187 handle = e.target ? e.target : e.srcElement;
188 Dygraph.addEvent(topElem, 'mousemove', onZoom);
189 Dygraph.addEvent(topElem, 'mouseup', onZoomEnd);
190 self.fgcanvas_.style.cursor = 'col-resize';
191 };
192
758a629f 193 onZoom = function(e) {
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194 if (!isZooming) {
195 return;
196 }
197 var delX = e.screenX - xLast;
198 if (Math.abs(delX) < 4) {
199 return;
200 }
201 xLast = e.screenX;
202 var zoomHandleStatus = self.getZoomHandleStatus_();
758a629f 203 var newPos;
ccd9d7c2 204 if (handle == self.leftZoomHandle_) {
758a629f 205 newPos = zoomHandleStatus.leftHandlePos + delX;
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206 newPos = Math.min(newPos, zoomHandleStatus.rightHandlePos - handle.width - 3);
207 newPos = Math.max(newPos, self.canvasRect_.x);
208 } else {
758a629f 209 newPos = zoomHandleStatus.rightHandlePos + delX;
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210 newPos = Math.min(newPos, self.canvasRect_.x + self.canvasRect_.w);
211 newPos = Math.max(newPos, zoomHandleStatus.leftHandlePos + handle.width + 3);
212 }
920208fb 213 var halfHandleWidth = handle.width/2;
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214 handle.style.left = (newPos - halfHandleWidth) + 'px';
215 self.drawInteractiveLayer_();
216
217 // Zoom on the fly (if not using excanvas).
920208fb 218 if (!self.isUsingExcanvas_) {
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219 doZoom();
220 }
221 };
222
758a629f 223 onZoomEnd = function(e) {
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224 if (!isZooming) {
225 return;
226 }
227 isZooming = false;
228 Dygraph.removeEvent(topElem, 'mousemove', onZoom);
229 Dygraph.removeEvent(topElem, 'mouseup', onZoomEnd);
230 self.fgcanvas_.style.cursor = 'default';
231
232 // If using excanvas, Zoom now.
920208fb 233 if (self.isUsingExcanvas_) {
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234 doZoom();
235 }
236 };
237
758a629f 238 doZoom = function() {
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239 try {
240 var zoomHandleStatus = self.getZoomHandleStatus_();
241 self.isChangingRange_ = true;
242 if (!zoomHandleStatus.isZoomed) {
243 self.dygraph_.doUnzoom_();
244 } else {
245 var xDataWindow = toXDataWindow(zoomHandleStatus);
246 self.dygraph_.doZoomXDates_(xDataWindow[0], xDataWindow[1]);
247 }
248 } finally {
249 self.isChangingRange_ = false;
250 }
251 };
252
758a629f 253 isMouseInPanZone = function(e) {
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254 if (self.isUsingExcanvas_) {
255 return e.srcElement == self.iePanOverlay_;
256 } else {
257 // Getting clientX directly from the event is not accurate enough :(
758a629f 258 var clientX = self.canvasRect_.x + (e.layerX !== undefined ? e.layerX : e.offsetX);
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259 var zoomHandleStatus = self.getZoomHandleStatus_();
260 return (clientX > zoomHandleStatus.leftHandlePos && clientX < zoomHandleStatus.rightHandlePos);
261 }
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262 };
263
758a629f 264 onPanStart = function(e) {
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265 if (!isPanning && isMouseInPanZone(e) && self.getZoomHandleStatus_().isZoomed) {
266 Dygraph.cancelEvent(e);
267 isPanning = true;
268 xLast = e.screenX;
269 Dygraph.addEvent(topElem, 'mousemove', onPan);
270 Dygraph.addEvent(topElem, 'mouseup', onPanEnd);
271 }
272 };
273
758a629f 274 onPan = function(e) {
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275 if (!isPanning) {
276 return;
277 }
920208fb 278 Dygraph.cancelEvent(e);
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279
280 var delX = e.screenX - xLast;
281 if (Math.abs(delX) < 4) {
282 return;
283 }
284 xLast = e.screenX;
285
286 // Move range view
287 var zoomHandleStatus = self.getZoomHandleStatus_();
288 var leftHandlePos = zoomHandleStatus.leftHandlePos;
289 var rightHandlePos = zoomHandleStatus.rightHandlePos;
290 var rangeSize = rightHandlePos - leftHandlePos;
291 if (leftHandlePos + delX <= self.canvasRect_.x) {
292 leftHandlePos = self.canvasRect_.x;
293 rightHandlePos = leftHandlePos + rangeSize;
294 } else if (rightHandlePos + delX >= self.canvasRect_.x + self.canvasRect_.w) {
295 rightHandlePos = self.canvasRect_.x + self.canvasRect_.w;
296 leftHandlePos = rightHandlePos - rangeSize;
297 } else {
298 leftHandlePos += delX;
299 rightHandlePos += delX;
300 }
920208fb 301 var halfHandleWidth = self.leftZoomHandle_.width/2;
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302 self.leftZoomHandle_.style.left = (leftHandlePos - halfHandleWidth) + 'px';
303 self.rightZoomHandle_.style.left = (rightHandlePos - halfHandleWidth) + 'px';
304 self.drawInteractiveLayer_();
305
306 // Do pan on the fly (if not using excanvas).
920208fb 307 if (!self.isUsingExcanvas_) {
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308 doPan();
309 }
310 };
311
758a629f 312 onPanEnd = function(e) {
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313 if (!isPanning) {
314 return;
315 }
316 isPanning = false;
317 Dygraph.removeEvent(topElem, 'mousemove', onPan);
318 Dygraph.removeEvent(topElem, 'mouseup', onPanEnd);
319 // If using excanvas, do pan now.
920208fb 320 if (self.isUsingExcanvas_) {
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321 doPan();
322 }
323 };
324
758a629f 325 doPan = function() {
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326 try {
327 self.isChangingRange_ = true;
328 self.dygraph_.dateWindow_ = toXDataWindow(self.getZoomHandleStatus_());
329 self.dygraph_.drawGraph_(false);
330 } finally {
331 self.isChangingRange_ = false;
332 }
333 };
334
758a629f 335 onCanvasMouseMove = function(e) {
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336 if (isZooming || isPanning) {
337 return;
338 }
339 var cursor = isMouseInPanZone(e) ? 'move' : 'default';
340 if (cursor != self.fgcanvas_.style.cursor) {
341 self.fgcanvas_.style.cursor = cursor;
342 }
343 };
344
345 var interactionModel = {
346 mousedown: function(event, g, context) {
347 context.initializeMouseDown(event, g, context);
348 Dygraph.startPan(event, g, context);
349 },
350 mousemove: function(event, g, context) {
351 if (context.isPanning) {
352 Dygraph.movePan(event, g, context);
353 }
354 },
355 mouseup: function(event, g, context) {
356 if (context.isPanning) {
357 Dygraph.endPan(event, g, context);
358 }
359 }
360 };
361
362 this.dygraph_.attrs_.interactionModel = interactionModel;
758a629f 363 this.dygraph_.attrs_.panEdgeFraction = 0.0001;
ccd9d7c2 364
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365 var dragStartEvent = window.opera ? 'mousedown' : 'dragstart';
366 Dygraph.addEvent(this.leftZoomHandle_, dragStartEvent, onZoomStart);
367 Dygraph.addEvent(this.rightZoomHandle_, dragStartEvent, onZoomStart);
368
369 if (this.isUsingExcanvas_) {
370 Dygraph.addEvent(this.iePanOverlay_, 'mousedown', onPanStart);
371 } else {
372 Dygraph.addEvent(this.fgcanvas_, 'mousedown', onPanStart);
373 Dygraph.addEvent(this.fgcanvas_, 'mousemove', onCanvasMouseMove);
374 }
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375};
376
377/**
378 * @private
379 * Draws the static layer in the background canvas.
380 */
381DygraphRangeSelector.prototype.drawStaticLayer_ = function() {
382 var ctx = this.bgcanvas_ctx_;
383 ctx.clearRect(0, 0, this.canvasRect_.w, this.canvasRect_.h);
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384 try {
385 this.drawMiniPlot_();
386 } catch(ex) {
5061b42f 387 Dygraph.warn(ex);
ccd9d7c2 388 }
920208fb 389
758a629f 390 var margin = 0.5;
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391 this.bgcanvas_ctx_.lineWidth = 1;
392 ctx.strokeStyle = 'gray';
393 ctx.beginPath();
394 ctx.moveTo(margin, margin);
395 ctx.lineTo(margin, this.canvasRect_.h-margin);
396 ctx.lineTo(this.canvasRect_.w-margin, this.canvasRect_.h-margin);
397 ctx.lineTo(this.canvasRect_.w-margin, margin);
398 ctx.stroke();
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399};
400
401
402/**
403 * @private
404 * Draws the mini plot in the background canvas.
405 */
406DygraphRangeSelector.prototype.drawMiniPlot_ = function() {
407 var fillStyle = this.attr_('rangeSelectorPlotFillColor');
408 var strokeStyle = this.attr_('rangeSelectorPlotStrokeColor');
409 if (!fillStyle && !strokeStyle) {
410 return;
411 }
412
413 var combinedSeriesData = this.computeCombinedSeriesAndLimits_();
414 var yRange = combinedSeriesData.yMax - combinedSeriesData.yMin;
415
416 // Draw the mini plot.
417 var ctx = this.bgcanvas_ctx_;
758a629f 418 var margin = 0.5;
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419
420 var xExtremes = this.dygraph_.xAxisExtremes();
421 var xRange = Math.max(xExtremes[1] - xExtremes[0], 1.e-30);
422 var xFact = (this.canvasRect_.w - margin)/xRange;
423 var yFact = (this.canvasRect_.h - margin)/yRange;
424 var canvasWidth = this.canvasRect_.w - margin;
425 var canvasHeight = this.canvasRect_.h - margin;
426
427 ctx.beginPath();
428 ctx.moveTo(margin, canvasHeight);
429 for (var i = 0; i < combinedSeriesData.data.length; i++) {
430 var dataPoint = combinedSeriesData.data[i];
431 var x = (dataPoint[0] - xExtremes[0])*xFact;
432 var y = canvasHeight - (dataPoint[1] - combinedSeriesData.yMin)*yFact;
433 if (isFinite(x) && isFinite(y)) {
434 ctx.lineTo(x, y);
435 }
436 }
437 ctx.lineTo(canvasWidth, canvasHeight);
438 ctx.closePath();
439
440 if (fillStyle) {
441 var lingrad = this.bgcanvas_ctx_.createLinearGradient(0, 0, 0, canvasHeight);
442 lingrad.addColorStop(0, 'white');
443 lingrad.addColorStop(1, fillStyle);
444 this.bgcanvas_ctx_.fillStyle = lingrad;
445 ctx.fill();
446 }
447
448 if (strokeStyle) {
449 this.bgcanvas_ctx_.strokeStyle = strokeStyle;
450 this.bgcanvas_ctx_.lineWidth = 1.5;
451 ctx.stroke();
452 }
453};
454
455/**
456 * @private
457 * Computes and returns the combinded series data along with min/max for the mini plot.
458 * @return {Object} An object containing combinded series array, ymin, ymax.
459 */
460DygraphRangeSelector.prototype.computeCombinedSeriesAndLimits_ = function() {
461 var data = this.dygraph_.rawData_;
462 var logscale = this.attr_('logscale');
463
464 // Create a combined series (average of all series values).
465 var combinedSeries = [];
466 var sum;
467 var count;
758a629f 468 var yVal, y;
ccd9d7c2 469 var mutipleValues = typeof data[0][1] != 'number';
758a629f 470 var i, j, k;
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471
472 if (mutipleValues) {
473 sum = [];
474 count = [];
758a629f 475 for (k = 0; k < data[0][1].length; k++) {
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476 sum.push(0);
477 count.push(0);
478 }
479 mutipleValues = true;
480 }
481
758a629f 482 for (i = 0; i < data.length; i++) {
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483 var dataPoint = data[i];
484 var xVal = dataPoint[0];
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485
486 if (mutipleValues) {
758a629f 487 for (k = 0; k < sum.length; k++) {
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488 sum[k] = count[k] = 0;
489 }
490 } else {
491 sum = count = 0;
492 }
493
758a629f 494 for (j = 1; j < dataPoint.length; j++) {
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495 if (this.dygraph_.visibility()[j-1]) {
496 if (mutipleValues) {
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497 for (k = 0; k < sum.length; k++) {
498 y = dataPoint[j][k];
499 if (y === null || isNaN(y)) continue;
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500 sum[k] += y;
501 count[k]++;
502 }
503 } else {
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504 y = dataPoint[j];
505 if (y === null || isNaN(y)) continue;
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506 sum += y;
507 count++;
508 }
509 }
510 }
511
512 if (mutipleValues) {
758a629f 513 for (k = 0; k < sum.length; k++) {
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514 sum[k] /= count[k];
515 }
516 yVal = sum.slice(0);
517 } else {
518 yVal = sum/count;
519 }
520
521 combinedSeries.push([xVal, yVal]);
522 }
523
524 // Account for roll period, fractions.
525 combinedSeries = this.dygraph_.rollingAverage(combinedSeries, this.dygraph_.rollPeriod_);
526
527 if (typeof combinedSeries[0][1] != 'number') {
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528 for (i = 0; i < combinedSeries.length; i++) {
529 yVal = combinedSeries[i][1];
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530 combinedSeries[i][1] = yVal[0];
531 }
532 }
533
534 // Compute the y range.
535 var yMin = Number.MAX_VALUE;
536 var yMax = -Number.MAX_VALUE;
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537 for (i = 0; i < combinedSeries.length; i++) {
538 yVal = combinedSeries[i][1];
539 if (yVal !== null && isFinite(yVal) && (!logscale || yVal > 0)) {
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540 yMin = Math.min(yMin, yVal);
541 yMax = Math.max(yMax, yVal);
542 }
543 }
544
545 // Convert Y data to log scale if needed.
546 // Also, expand the Y range to compress the mini plot a little.
758a629f 547 var extraPercent = 0.25;
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548 if (logscale) {
549 yMax = Dygraph.log10(yMax);
550 yMax += yMax*extraPercent;
551 yMin = Dygraph.log10(yMin);
758a629f 552 for (i = 0; i < combinedSeries.length; i++) {
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553 combinedSeries[i][1] = Dygraph.log10(combinedSeries[i][1]);
554 }
555 } else {
556 var yExtra;
5061b42f 557 var yRange = yMax - yMin;
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558 if (yRange <= Number.MIN_VALUE) {
559 yExtra = yMax*extraPercent;
560 } else {
561 yExtra = yRange*extraPercent;
562 }
563 yMax += yExtra;
564 yMin -= yExtra;
565 }
566
567 return {data: combinedSeries, yMin: yMin, yMax: yMax};
568};
569
570/**
571 * @private
572 * Places the zoom handles in the proper position based on the current X data window.
573 */
574DygraphRangeSelector.prototype.placeZoomHandles_ = function() {
575 var xExtremes = this.dygraph_.xAxisExtremes();
576 var xWindowLimits = this.dygraph_.xAxisRange();
577 var xRange = xExtremes[1] - xExtremes[0];
578 var leftPercent = Math.max(0, (xWindowLimits[0] - xExtremes[0])/xRange);
579 var rightPercent = Math.max(0, (xExtremes[1] - xWindowLimits[1])/xRange);
580 var leftCoord = this.canvasRect_.x + this.canvasRect_.w*leftPercent;
581 var rightCoord = this.canvasRect_.x + this.canvasRect_.w*(1 - rightPercent);
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582 var handleTop = Math.max(this.canvasRect_.y, this.canvasRect_.y + (this.canvasRect_.h - this.leftZoomHandle_.height)/2);
583 var halfHandleWidth = this.leftZoomHandle_.width/2;
584 this.leftZoomHandle_.style.left = (leftCoord - halfHandleWidth) + 'px';
ccd9d7c2 585 this.leftZoomHandle_.style.top = handleTop + 'px';
920208fb 586 this.rightZoomHandle_.style.left = (rightCoord - halfHandleWidth) + 'px';
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587 this.rightZoomHandle_.style.top = this.leftZoomHandle_.style.top;
588
589 this.leftZoomHandle_.style.visibility = 'visible';
590 this.rightZoomHandle_.style.visibility = 'visible';
591};
592
593/**
594 * @private
595 * Draws the interactive layer in the foreground canvas.
596 */
597DygraphRangeSelector.prototype.drawInteractiveLayer_ = function() {
598 var ctx = this.fgcanvas_ctx_;
599 ctx.clearRect(0, 0, this.canvasRect_.w, this.canvasRect_.h);
600 var margin = 1;
601 var width = this.canvasRect_.w - margin;
602 var height = this.canvasRect_.h - margin;
603 var zoomHandleStatus = this.getZoomHandleStatus_();
604
605 ctx.strokeStyle = 'black';
606 if (!zoomHandleStatus.isZoomed) {
607 ctx.beginPath();
608 ctx.moveTo(margin, margin);
609 ctx.lineTo(margin, height);
610 ctx.lineTo(width, height);
611 ctx.lineTo(width, margin);
612 ctx.stroke();
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613 if (this.iePanOverlay_) {
614 this.iePanOverlay_.style.display = 'none';
615 }
ccd9d7c2 616 } else {
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617 var leftHandleCanvasPos = Math.max(margin, zoomHandleStatus.leftHandlePos - this.canvasRect_.x);
618 var rightHandleCanvasPos = Math.min(width, zoomHandleStatus.rightHandlePos - this.canvasRect_.x);
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619
620 ctx.fillStyle = 'rgba(240, 240, 240, 0.6)';
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621 ctx.fillRect(0, 0, leftHandleCanvasPos, this.canvasRect_.h);
622 ctx.fillRect(rightHandleCanvasPos, 0, this.canvasRect_.w - rightHandleCanvasPos, this.canvasRect_.h);
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623
624 ctx.beginPath();
625 ctx.moveTo(margin, margin);
626 ctx.lineTo(leftHandleCanvasPos, margin);
627 ctx.lineTo(leftHandleCanvasPos, height);
628 ctx.lineTo(rightHandleCanvasPos, height);
629 ctx.lineTo(rightHandleCanvasPos, margin);
630 ctx.lineTo(width, margin);
631 ctx.stroke();
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632
633 if (this.isUsingExcanvas_) {
634 this.iePanOverlay_.style.width = (rightHandleCanvasPos - leftHandleCanvasPos) + 'px';
635 this.iePanOverlay_.style.left = leftHandleCanvasPos + 'px';
636 this.iePanOverlay_.style.height = height + 'px';
637 this.iePanOverlay_.style.display = 'inline';
638 }
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639 }
640};
641
642/**
643 * @private
644 * Returns the current zoom handle position information.
645 * @return {Object} The zoom handle status.
646 */
647DygraphRangeSelector.prototype.getZoomHandleStatus_ = function() {
920208fb 648 var halfHandleWidth = this.leftZoomHandle_.width/2;
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649 var leftHandlePos = parseInt(this.leftZoomHandle_.style.left, 10) + halfHandleWidth;
650 var rightHandlePos = parseInt(this.rightZoomHandle_.style.left, 10) + halfHandleWidth;
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651 return {
652 leftHandlePos: leftHandlePos,
653 rightHandlePos: rightHandlePos,
654 isZoomed: (leftHandlePos - 1 > this.canvasRect_.x || rightHandlePos + 1 < this.canvasRect_.x+this.canvasRect_.w)
655 };
656};