lerpArray.js

var a = [1,2,3,4,9,20];
a.lerp = function(n){ 
  var a = this[Math.floor(n)]; 
    //console.log("a: " + a); 
  var b = this[Math.ceil(n)];
    //console.log("b: " + b); 
  var t = n-Math.floor(n); 
    //console.log("t: " + t); 
  return (1-t)*a + t*b;
}
console.log(a.lerp(4.5))
//could be expanded to bezier, maybe b splines too.
//The idea was to have a[4.5] be an alias for a.lerp(4.5)
//but I suppose this works...

Oops, accidentally created this while anonymous >.<