Simple JavaScript Scale

README.md

I love D3's Quantitative Scales and wanted a simple way to create and use scales in that style.

Example

var centigradeToFahrenheit = new Scale().domain(-40, 0).range(-40, 32);
var fahrenheitToCentigrade = new Scale().domain(-40, 32).range(-40, 0);

centigradeToFahrenheit(35); // 95 hot!
fahrenheitToCentigrade(14); // -10 cold!

sideburns.js

// This is a function
function Normalizer(min, max) {
  return function(val) {
    return (val - min) / (max - min);
  }
}

// This is another
function Interpolater(min, max, clamp) {
  return function(val) {
    val = min + (max - min) * val;
    return clamp ? Math.min(Math.max(val, min), max) : val;
  }
}

// This is a third
function Scale() {
  var domain = new Normalizer(0, 1);
  var range = new Interpolater(0, 1);
  var s = function(val) {
    return range(domain(val));
  };
  s.domain = function(min, max) {
    if (!arguments.length) return domain;
    domain = new Normalizer(min, max)
    return s
  };
  s.range = function(min, max, clamp) {
    if (!arguments.length) return range;
    range = new Interpolater(min, max, clamp)
    return s
  };
  return s;
}

// Now form a visualization
// ========================

thumbnail.png