code: function(r, g, b) {
              if (isArray(r)) {
                  return this.rgb2hex.apply(this, r);
              }
  
              var f=this.dec2hex;
              return f(r) + f(g) + f(b);
          }
docs: Converts decimal rgb values into a hex string
  255,255,255 -> FFFFFF
  @method rgb2hex
  @param r {int|[int, int, int]} the red value, or an
  array containing all three parameters
  @param g {int} the green value
  @param b {int} the blue value
  @return {string} the hex string