diff -r efd9c589177a -r c0b4a8b5a012 toolkit/javascript/d3/src/core/split.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/javascript/d3/src/core/split.js	Thu Apr 10 14:20:23 2014 +0200
@@ -0,0 +1,21 @@
+d3.split = function(array, f) {
+  var arrays = [],
+      values = [],
+      value,
+      i = -1,
+      n = array.length;
+  if (arguments.length < 2) f = d3_splitter;
+  while (++i < n) {
+    if (f.call(values, value = array[i], i)) {
+      values = [];
+    } else {
+      if (!values.length) arrays.push(values);
+      values.push(value);
+    }
+  }
+  return arrays;
+};
+
+function d3_splitter(d) {
+  return d == null;
+}