Quick linear scale inspired by d3.js scales, based on the processing.org map() function.takes in an object with a domain array and a rage array, gives you back a function that receives a value and returns the scaled value.

linearScale.js

// based on https://github.com/processing/processing/blob/a6e0e227a948e7e2dc042c04504d6f5b8cf0c1a6/core/src/processing/core/PApplet.java#L5093

var scale = function(opts){
  var istart = opts.domain[0],
      istop  = opts.domain[1],
      ostart = opts.range[0],
      ostop  = opts.range[1];

  return function scale(value) {
    return ostart + (ostop - ostart) * ((value - istart) / (istop - istart));
  }
};