--- /dev/null
+/* Flot plugin for stacking data sets rather than overlyaing them.
+
+Copyright (c) 2007-2013 IOLA and Ole Laursen.
+Licensed under the MIT license.
+
+The plugin assumes the data is sorted on x (or y if stacking horizontally).
+For line charts, it is assumed that if a line has an undefined gap (from a
+null point), then the line above it should have the same gap - insert zeros
+instead of "null" if you want another behaviour. This also holds for the start
+and end of the chart. Note that stacking a mix of positive and negative values
+in most instances doesn't make sense (so it looks weird).
+
+Two or more series are stacked when their "stack" attribute is set to the same
+key (which can be any number or string or just "true"). To specify the default
+stack, you can set the stack option like this:
+
+ series: {
+ stack: null/false, true, or a key (number/string)
+ }
+
+You can also specify it for a single series, like this:
+
+ $.plot( $("#placeholder"), [{
+ data: [ ... ],
+ stack: true
+ }])
+
+The stacking order is determined by the order of the data series in the array
+(later series end up on top of the previous).
+
+Internally, the plugin modifies the datapoints in each series, adding an
+offset to the y value. For line series, extra data points are inserted through
+interpolation. If there's a second y value, it's also adjusted (e.g for bar
+charts or filled areas).
+
+*/
+
+(function ($) {
+ var options = {
+ series: { stack: null } // or number/string
+ };
+
+ function init(plot) {
+ function findMatchingSeries(s, allseries) {
+ var res = null;
+ for (var i = 0; i < allseries.length; ++i) {
+ if (s == allseries[i])
+ break;
+
+ if (allseries[i].stack == s.stack)
+ res = allseries[i];
+ }
+
+ return res;
+ }
+
+ function stackData(plot, s, datapoints) {
+ if (s.stack == null || s.stack === false)
+ return;
+
+ var other = findMatchingSeries(s, plot.getData());
+ if (!other)
+ return;
+
+ var ps = datapoints.pointsize,
+ points = datapoints.points,
+ otherps = other.datapoints.pointsize,
+ otherpoints = other.datapoints.points,
+ newpoints = [],
+ px, py, intery, qx, qy, bottom,
+ withlines = s.lines.show,
+ horizontal = s.bars.horizontal,
+ withbottom = ps > 2 && (horizontal ? datapoints.format[2].x : datapoints.format[2].y),
+ withsteps = withlines && s.lines.steps,
+ fromgap = true,
+ keyOffset = horizontal ? 1 : 0,
+ accumulateOffset = horizontal ? 0 : 1,
+ i = 0, j = 0, l, m;
+
+ while (true) {
+ if (i >= points.length)
+ break;
+
+ l = newpoints.length;
+
+ if (points[i] == null) {
+ // copy gaps
+ for (m = 0; m < ps; ++m)
+ newpoints.push(points[i + m]);
+ i += ps;
+ }
+ else if (j >= otherpoints.length) {
+ // for lines, we can't use the rest of the points
+ if (!withlines) {
+ for (m = 0; m < ps; ++m)
+ newpoints.push(points[i + m]);
+ }
+ i += ps;
+ }
+ else if (otherpoints[j] == null) {
+ // oops, got a gap
+ for (m = 0; m < ps; ++m)
+ newpoints.push(null);
+ fromgap = true;
+ j += otherps;
+ }
+ else {
+ // cases where we actually got two points
+ px = points[i + keyOffset];
+ py = points[i + accumulateOffset];
+ qx = otherpoints[j + keyOffset];
+ qy = otherpoints[j + accumulateOffset];
+ bottom = 0;
+
+ if (px == qx) {
+ for (m = 0; m < ps; ++m)
+ newpoints.push(points[i + m]);
+
+ newpoints[l + accumulateOffset] += qy;
+ bottom = qy;
+
+ i += ps;
+ j += otherps;
+ }
+ else if (px > qx) {
+ // we got past point below, might need to
+ // insert interpolated extra point
+ if (withlines && i > 0 && points[i - ps] != null) {
+ intery = py + (points[i - ps + accumulateOffset] - py) * (qx - px) / (points[i - ps + keyOffset] - px);
+ newpoints.push(qx);
+ newpoints.push(intery + qy);
+ for (m = 2; m < ps; ++m)
+ newpoints.push(points[i + m]);
+ bottom = qy;
+ }
+
+ j += otherps;
+ }
+ else { // px < qx
+ if (fromgap && withlines) {
+ // if we come from a gap, we just skip this point
+ i += ps;
+ continue;
+ }
+
+ for (m = 0; m < ps; ++m)
+ newpoints.push(points[i + m]);
+
+ // we might be able to interpolate a point below,
+ // this can give us a better y
+ if (withlines && j > 0 && otherpoints[j - otherps] != null)
+ bottom = qy + (otherpoints[j - otherps + accumulateOffset] - qy) * (px - qx) / (otherpoints[j - otherps + keyOffset] - qx);
+
+ newpoints[l + accumulateOffset] += bottom;
+
+ i += ps;
+ }
+
+ fromgap = false;
+
+ if (l != newpoints.length && withbottom)
+ newpoints[l + 2] += bottom;
+ }
+
+ // maintain the line steps invariant
+ if (withsteps && l != newpoints.length && l > 0
+ && newpoints[l] != null
+ && newpoints[l] != newpoints[l - ps]
+ && newpoints[l + 1] != newpoints[l - ps + 1]) {
+ for (m = 0; m < ps; ++m)
+ newpoints[l + ps + m] = newpoints[l + m];
+ newpoints[l + 1] = newpoints[l - ps + 1];
+ }
+ }
+
+ datapoints.points = newpoints;
+ }
+
+ plot.hooks.processDatapoints.push(stackData);
+ }
+
+ $.plot.plugins.push({
+ init: init,
+ options: options,
+ name: 'stack',
+ version: '1.2'
+ });
+})(jQuery);
Code Review / stor4nfv.git / blobdiff