diff -r efd9c589177a -r c0b4a8b5a012 toolkit/javascript/d3/examples/stream/stream.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/javascript/d3/examples/stream/stream.js	Thu Apr 10 14:20:23 2014 +0200
@@ -0,0 +1,42 @@
+var n = 20, // number of layers
+    m = 200, // number of samples per layer
+    data0 = d3.layout.stack().offset("wiggle")(stream_layers(n, m)),
+    data1 = d3.layout.stack().offset("wiggle")(stream_layers(n, m)),
+    color = d3.interpolateRgb("#aad", "#556");
+
+var w = 960,
+    h = 500,
+    mx = m - 1,
+    my = d3.max(data0.concat(data1), function(d) {
+      return d3.max(d, function(d) {
+        return d.y0 + d.y;
+      });
+    });
+
+var area = d3.svg.area()
+    .x(function(d) { return d.x * w / mx; })
+    .y0(function(d) { return h - d.y0 * h / my; })
+    .y1(function(d) { return h - (d.y + d.y0) * h / my; });
+
+var vis = d3.select("#chart")
+  .append("svg:svg")
+    .attr("width", w)
+    .attr("height", h);
+
+vis.selectAll("path")
+    .data(data0)
+  .enter().append("svg:path")
+    .style("fill", function() { return color(Math.random()); })
+    .attr("d", area);
+
+function transition() {
+  d3.selectAll("path")
+      .data(function() {
+        var d = data1;
+        data1 = data0;
+        return data0 = d;
+      })
+    .transition()
+      .duration(2500)
+      .attr("d", area);
+}