plotkit_v091/PlotKit/Layout.js

   1 /*
   2     PlotKit Layout
   3     ==============
   4
   5     Handles laying out data on to a virtual canvas square canvas between 0.0
   6     and 1.0. If you want to add new chart/plot types such as point plots,
   7     you need to add them here.
   8
   9     Copyright
  10     ---------
  11     Copyright 2005,2006 (c) Alastair Tse <alastair^liquidx.net>
  12     For use under the BSD license. <http://www.liquidx.net/plotkit>
  13
  14 */
  15
  16 try {
  17     if (typeof(PlotKit.Base) == 'undefined')
  18     {
  19         throw ""
  20     }
  21 }
  22 catch (e) {
  23     throw "PlotKit.Layout depends on MochiKit.{Base,Color,DOM,Format} and PlotKit.Base"
  24 }
  25
  26 // --------------------------------------------------------------------
  27 // Start of Layout definition
  28 // --------------------------------------------------------------------
  29
  30 if (typeof(PlotKit.Layout) == 'undefined') {
  31     PlotKit.Layout = {};
  32 }
  33
  34 PlotKit.Layout.NAME = "PlotKit.Layout";
  35 PlotKit.Layout.VERSION = PlotKit.VERSION;
  36
  37 PlotKit.Layout.__repr__ = function() {
  38     return "[" + this.NAME + " " + this.VERSION + "]";
  39 };
  40
  41 PlotKit.Layout.toString = function() {
  42     return this.__repr__();
  43 }
  44
  45 PlotKit.Layout.valid_styles = ["bar", "line", "pie", "point"];
  46
  47 // --------------------------------------------------------------------
  48 // Start of Layout definition
  49 // --------------------------------------------------------------------
  50
  51 PlotKit.Layout = function(style, options) {
  52
  53     this.options = {
  54         "barWidthFillFraction": 0.75,
  55         "barOrientation": "vertical",
  56         "xOriginIsZero": true,
  57         "yOriginIsZero": true,
  58         "xAxis": null, // [xmin, xmax]
  59         "yAxis": null, // [ymin, ymax]
  60         "xTicks": null, // [{label: "somelabel", v: value}, ..] (label opt.)
  61         "yTicks": null, // [{label: "somelabel", v: value}, ..] (label opt.)
  62         "xNumberOfTicks": 10,
  63         "yNumberOfTicks": 5,
  64         "xTickPrecision": 1,
  65         "yTickPrecision": 1,
  66         "pieRadius": 0.4
  67     };
  68
  69     // valid external options : TODO: input verification
  70     this.style = style;
  71     MochiKit.Base.update(this.options, options ? options : {});
  72
  73     // externally visible states
  74     // overriden if xAxis and yAxis are set in options
  75     if (!MochiKit.Base.isUndefinedOrNull(this.options.xAxis)) {
  76         this.minxval = this.options.xAxis[0];
  77         this.maxxval = this.options.xAxis[1];
  78         this.xscale = this.maxxval - this.minxval;
  79     }
  80     else {
  81         this.minxval = 0;
  82         this.maxxval = null;
  83         this.xscale = null; // val -> pos factor (eg, xval * xscale = xpos)
  84     }
  85
  86     if (!MochiKit.Base.isUndefinedOrNull(this.options.yAxis)) {
  87         this.minyval = this.options.yAxis[0];
  88         this.maxyval = this.options.yAxis[1];
  89         this.yscale = this.maxyval - this.minyval;
  90     }
  91     else {
  92         this.minyval = 0;
  93         this.maxyval = null;
  94         this.yscale = null;
  95     }
  96
  97     this.bars = new Array();   // array of bars to plot for bar charts
  98     this.points = new Array(); // array of points to plot for line plots
  99     this.slices = new Array(); // array of slices to draw for pie charts
 100
 101     this.xticks = new Array();
 102     this.yticks = new Array();
 103
 104     // internal states
 105     this.datasets = new Array();
 106     this.minxdelta = 0;
 107     this.xrange = 1;
 108     this.yrange = 1;
 109
 110     this.hitTestCache = {x2maxy: null};
 111
 112 };
 113
 114 // --------------------------------------------------------------------
 115 // Dataset Manipulation
 116 // --------------------------------------------------------------------
 117
 118
 119 PlotKit.Layout.prototype.addDataset = function(setname, set_xy) {
 120     this.datasets[setname] = set_xy;
 121 };
 122
 123 PlotKit.Layout.prototype.removeDataset = function(setname, set_xy) {
 124     delete this.datasets[setname];
 125 };
 126
 127 PlotKit.Layout.prototype.addDatasetFromTable = function(name, tableElement, xcol, ycol,  lcol) {
 128         var isNil = MochiKit.Base.isUndefinedOrNull;
 129         var scrapeText = MochiKit.DOM.scrapeText;
 130         var strip = MochiKit.Format.strip;
 131
 132         if (isNil(xcol))
 133                 xcol = 0;
 134         if (isNil(ycol))
 135                 ycol = 1;
 136         if (isNil(lcol))
 137             lcol = -1;
 138
 139     var rows = tableElement.tBodies[0].rows;
 140     var data = new Array();
 141     var labels = new Array();
 142
 143     if (!isNil(rows)) {
 144         for (var i = 0; i < rows.length; i++) {
 145             data.push([parseFloat(strip(scrapeText(rows[i].cells[xcol]))),
 146                        parseFloat(strip(scrapeText(rows[i].cells[ycol])))]);
 147             if (lcol >= 0){
 148                labels.push({v: parseFloat(strip(scrapeText(rows[i].cells[xcol]))),
 149                             label:  strip(scrapeText(rows[i].cells[lcol]))});
 150             }
 151         }
 152         this.addDataset(name, data);
 153         if (lcol >= 0) {
 154             this.options.xTicks = labels;
 155         }
 156         return true;
 157     }
 158     return false;
 159 };
 160
 161 // --------------------------------------------------------------------
 162 // Evaluates the layout for the current data and style.
 163 // --------------------------------------------------------------------
 164
 165 PlotKit.Layout.prototype.evaluate = function() {
 166     this._evaluateLimits();
 167     this._evaluateScales();
 168     if (this.style == "line") {
 169         this._evaluateLineCharts();
 170         this._evaluateLineTicks();
 171     }
 172 };
 173
 174
 175
 176
 177 // --------------------------------------------------------------------
 178 // START Internal Functions
 179 // --------------------------------------------------------------------
 180
 181 PlotKit.Layout.prototype._evaluateLimits = function() {
 182     // take all values from all datasets and find max and min
 183     var map = PlotKit.Base.map;
 184     var items = PlotKit.Base.items;
 185     var itemgetter = MochiKit.Base.itemgetter;
 186     var collapse = PlotKit.Base.collapse;
 187     var listMin = MochiKit.Base.listMin;
 188     var listMax = MochiKit.Base.listMax;
 189     var isNil = MochiKit.Base.isUndefinedOrNull;
 190
 191
 192     var all = collapse(map(itemgetter(1), items(this.datasets)));
 193     if (isNil(this.options.xAxis)) {
 194         if (this.options.xOriginIsZero)
 195             this.minxval = 0;
 196         else
 197             this.minxval = listMin(map(parseFloat, map(itemgetter(0), all)));
 198
 199         this.maxxval = listMax(map(parseFloat, map(itemgetter(0), all)));
 200     }
 201     else {
 202         this.minxval = this.options.xAxis[0];
 203         this.maxxval = this.options.xAxis[1];
 204         this.xscale = this.maxval - this.minxval;
 205     }
 206
 207     if (isNil(this.options.yAxis)) {
 208         if (this.options.yOriginIsZero)
 209             this.minyval = 0;
 210         else
 211             this.minyval = listMin(map(parseFloat, map(itemgetter(1), all)));
 212
 213         this.maxyval = listMax(map(parseFloat, map(itemgetter(1), all)));
 214     }
 215     else {
 216         this.minyval = this.options.yAxis[0];
 217         this.maxyval = this.options.yAxis[1];
 218         this.yscale = this.maxyval - this.minyval;
 219     }
 220
 221 };
 222
 223 PlotKit.Layout.prototype._evaluateScales = function() {
 224     var isNil = MochiKit.Base.isUndefinedOrNull;
 225
 226     this.xrange = this.maxxval - this.minxval;
 227     if (this.xrange == 0)
 228         this.xscale = 1.0;
 229     else
 230         this.xscale = 1/this.xrange;
 231
 232     this.yrange = this.maxyval - this.minyval;
 233     if (this.yrange == 0)
 234         this.yscale = 1.0;
 235     else
 236         this.yscale = 1/this.yrange;
 237 };
 238
 239 PlotKit.Layout.prototype._uniqueXValues = function() {
 240     var collapse = PlotKit.Base.collapse;
 241     var map = PlotKit.Base.map;
 242     var uniq = PlotKit.Base.uniq;
 243     var getter = MochiKit.Base.itemgetter;
 244     var items = PlotKit.Base.items;
 245
 246     var xvalues = map(parseFloat, map(getter(0), collapse(map(getter(1), items(this.datasets)))));
 247     xvalues.sort(MochiKit.Base.compare);
 248     return uniq(xvalues);
 249 };
 250
 251
 252 // Create the line charts
 253 PlotKit.Layout.prototype._evaluateLineCharts = function() {
 254     var items = PlotKit.Base.items;
 255
 256     var setCount = items(this.datasets).length;
 257
 258     // add all the rects
 259     this.points = new Array();
 260     var i = 0;
 261     for (var setName in this.datasets) {
 262         var dataset = this.datasets[setName];
 263         if (PlotKit.Base.isFuncLike(dataset)) continue;
 264         dataset.sort(function(a, b) { return compare(parseFloat(a[0]), parseFloat(b[0])); });
 265         for (var j = 0; j < dataset.length; j++) {
 266             var item = dataset[j];
 267             var point = {
 268                 x: ((parseFloat(item[0]) - this.minxval) * this.xscale),
 269                 y: 1.0 - ((parseFloat(item[1]) - this.minyval) * this.yscale),
 270                 xval: parseFloat(item[0]),
 271                 yval: parseFloat(item[1]),
 272                 name: setName
 273             };
 274
 275             // limit the x, y values so they do not overdraw
 276             if (point.y <= 0.0) {
 277                 point.y = 0.0;
 278             }
 279             if (point.y >= 1.0) {
 280                 point.y = 1.0;
 281             }
 282             if ((point.x >= 0.0) && (point.x <= 1.0)) {
 283                 this.points.push(point);
 284             }
 285         }
 286         i++;
 287     }
 288 };
 289
 290
 291 PlotKit.Layout.prototype._evaluateLineTicksForXAxis = function() {
 292     var isNil = MochiKit.Base.isUndefinedOrNull;
 293
 294     if (this.options.xTicks) {
 295         // we use use specified ticks with optional labels
 296
 297         this.xticks = new Array();
 298         var makeTicks = function(tick) {
 299             var label = tick.label;
 300             if (isNil(label))
 301                 label = tick.v.toString();
 302             var pos = this.xscale * (tick.v - this.minxval);
 303             if ((pos >= 0.0) && (pos <= 1.0)) {
 304                 this.xticks.push([pos, label]);
 305             }
 306         };
 307         MochiKit.Iter.forEach(this.options.xTicks, bind(makeTicks, this));
 308     }
 309     else if (this.options.xNumberOfTicks) {
 310         // we use defined number of ticks as hint to auto generate
 311         var xvalues = this._uniqueXValues();
 312         var roughSeparation = this.xrange / this.options.xNumberOfTicks;
 313         var tickCount = 0;
 314
 315         this.xticks = new Array();
 316         for (var i = 0; i <= xvalues.length; i++) {
 317             if ((xvalues[i] - this.minxval) >= (tickCount * roughSeparation)) {
 318                 var pos = this.xscale * (xvalues[i] - this.minxval);
 319                 if ((pos > 1.0) || (pos < 0.0))
 320                     continue;
 321                 this.xticks.push([pos, xvalues[i]]);
 322                 tickCount++;
 323             }
 324             if (tickCount > this.options.xNumberOfTicks)
 325                 break;
 326         }
 327     }
 328 };
 329
 330 PlotKit.Layout.prototype._evaluateLineTicksForYAxis = function() {
 331     var isNil = MochiKit.Base.isUndefinedOrNull;
 332
 333
 334     if (this.options.yTicks) {
 335         this.yticks = new Array();
 336         var makeTicks = function(tick) {
 337             var label = tick.label;
 338             if (isNil(label))
 339                 label = tick.v.toString();
 340             var pos = 1.0 - (this.yscale * (tick.v - this.minyval));
 341             if ((pos >= 0.0) && (pos <= 1.0)) {
 342                 this.yticks.push([pos, label]);
 343             }
 344         };
 345         MochiKit.Iter.forEach(this.options.yTicks, bind(makeTicks, this));
 346     }
 347     else if (this.options.yNumberOfTicks) {
 348         // We use the optionally defined number of ticks as a guide
 349         this.yticks = new Array();
 350
 351         // if we get this separation right, we'll have good looking graphs
 352         var roundInt = PlotKit.Base.roundInterval;
 353         var prec = this.options.yTickPrecision;
 354         var roughSeparation = roundInt(this.yrange,
 355                                        this.options.yNumberOfTicks, prec);
 356
 357         // round off each value of the y-axis to the precision
 358         // eg. 1.3333 at precision 1 -> 1.3
 359         for (var i = 0; i <= this.options.yNumberOfTicks; i++) {
 360             var yval = this.minyval + (i * roughSeparation);
 361             var pos = 1.0 - ((yval - this.minyval) * this.yscale);
 362             if ((pos > 1.0) || (pos < 0.0))
 363                 continue;
 364             this.yticks.push([pos, MochiKit.Format.roundToFixed(yval, prec)]);
 365         }
 366     }
 367 };
 368
 369 PlotKit.Layout.prototype._evaluateLineTicks = function() {
 370     this._evaluateLineTicksForXAxis();
 371     this._evaluateLineTicksForYAxis();
 372 };
 373
 374
 375 // --------------------------------------------------------------------
 376 // END Internal Functions
 377 // --------------------------------------------------------------------
 378
 379
 380 // Namespace Iniitialisation
 381
 382 PlotKit.LayoutModule = {};
 383 PlotKit.LayoutModule.Layout = PlotKit.Layout;
 384
 385 PlotKit.LayoutModule.EXPORT = [
 386     "Layout"
 387 ];
 388
 389 PlotKit.LayoutModule.EXPORT_OK = [];
 390
 391 PlotKit.LayoutModule.__new__ = function() {
 392     var m = MochiKit.Base;
 393
 394     m.nameFunctions(this);
 395
 396     this.EXPORT_TAGS = {
 397         ":common": this.EXPORT,
 398         ":all": m.concat(this.EXPORT, this.EXPORT_OK)
 399     };
 400 };
 401
 402 PlotKit.LayoutModule.__new__();
 403 MochiKit.Base._exportSymbols(this, PlotKit.LayoutModule);
 404
 405