+ // For stacked graphs, a NaN value for any point in the sum should create a
+ // clean gap in the graph. Back-propagate NaNs to all points at this X value.
+ if (this.attr_("stackedGraph")) {
+ for (k = datasets.length - 1; k >= 0; --k) {
+ // Use the first nonempty dataset to get X values.
+ if (!datasets[k]) continue;
+ for (j = 0; j < datasets[k].length; j++) {
+ var x = datasets[k][j][0];
+ if (isNaN(cumulative_y[x])) {
+ // Set all Y values to NaN at that X value.
+ for (i = datasets.length - 1; i >= 0; i--) {
+ if (!datasets[i]) continue;
+ datasets[i][j][1] = NaN;
+ }
+ }
+ }
+ break;
+ }
+ }
+
+ return [ datasets, extremes, boundaryIds ];
+};
+
+/**
+ * Update the graph with new data. This method is called when the viewing area
+ * has changed. If the underlying data or options have changed, predraw_ will
+ * be called before drawGraph_ is called.
+ *
+ * @private
+ */
+Dygraph.prototype.drawGraph_ = function() {
+ var start = new Date();
+
+ // This is used to set the second parameter to drawCallback, below.
+ var is_initial_draw = this.is_initial_draw_;
+ this.is_initial_draw_ = false;
+
+ this.layout_.removeAllDatasets();
+ this.setColors_();
+ this.attrs_.pointSize = 0.5 * this.attr_('highlightCircleSize');
+
+ var packed = this.gatherDatasets_(this.rolledSeries_, this.dateWindow_);
+ var datasets = packed[0];
+ var extremes = packed[1];
+ this.boundaryIds_ = packed[2];
+
+ this.setIndexByName_ = {};
+ var labels = this.attr_("labels");
+ if (labels.length > 0) {
+ this.setIndexByName_[labels[0]] = 0;
+ }
+ var dataIdx = 0;