diff -r efd9c589177a -r c0b4a8b5a012 toolkit/javascript/d3/src/scale/pow.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/javascript/d3/src/scale/pow.js	Thu Apr 10 14:20:23 2014 +0200
@@ -0,0 +1,54 @@
+d3.scale.pow = function() {
+  return d3_scale_pow(d3.scale.linear(), 1);
+};
+
+function d3_scale_pow(linear, exponent) {
+  var powp = d3_scale_powPow(exponent),
+      powb = d3_scale_powPow(1 / exponent);
+
+  function scale(x) {
+    return linear(powp(x));
+  }
+
+  scale.invert = function(x) {
+    return powb(linear.invert(x));
+  };
+
+  scale.domain = function(x) {
+    if (!arguments.length) return linear.domain().map(powb);
+    linear.domain(x.map(powp));
+    return scale;
+  };
+
+  scale.ticks = function(m) {
+    return d3_scale_linearTicks(scale.domain(), m);
+  };
+
+  scale.tickFormat = function(m) {
+    return d3_scale_linearTickFormat(scale.domain(), m);
+  };
+
+  scale.nice = function() {
+    return scale.domain(d3_scale_nice(scale.domain(), d3_scale_linearNice));
+  };
+
+  scale.exponent = function(x) {
+    if (!arguments.length) return exponent;
+    var domain = scale.domain();
+    powp = d3_scale_powPow(exponent = x);
+    powb = d3_scale_powPow(1 / exponent);
+    return scale.domain(domain);
+  };
+
+  scale.copy = function() {
+    return d3_scale_pow(linear.copy(), exponent);
+  };
+
+  return d3_scale_linearRebind(scale, linear);
+};
+
+function d3_scale_powPow(e) {
+  return function(x) {
+    return x < 0 ? -Math.pow(-x, e) : Math.pow(x, e);
+  };
+}