monte carlo solution

montecarlo.js

var integrate = function() {

  // return 42;

  var iters = 2000;
 
  var d = getGraphDimensions();
  var width = d.x.max - d.x.min;
  var height = d.y.max - d.y.min;
  var xmin = d.x.min;
  var ymin = d.y.min;

  var hits = 0;
 
  for (var i = 0; i < iters; i++) {
    var x = Math.random()*width + xmin;
    var y = Math.random()*height + ymin;
 
    if (evalPoint(x, y)) hits++;
  }
 
  var boxArea = width*height;
  return boxArea*hits/iters;

};