code: function render(plotFunction) {
    var data = [];
    for (var x = -10; x <= 10; x+= 0.1) {
      var y = plotFunction({x:x}); // <-- Execute Filtrex expression from user
      data.push([x, y]);
    }
    $.plot($('.plot'), [data], {});
    $('.plot').show();
  }
docs: Render plotFunction. Uses http://www.flotcharts.org/