git.r.bdr.sh - rbdr/dotfiles/blob

   1 // Thanks for hints: https://github.com/paulmillr/es6-shim
   2
   3 'use strict';
   4
   5 var some = Array.prototype.some, abs = Math.abs, sqrt = Math.sqrt
   6
   7   , compare = function (a, b) { return b - a; }
   8   , divide = function (x) { return x / this; }
   9   , add = function (sum, number) { return sum + number * number; };
  10
  11 module.exports = function (val1, val2/*, …valn*/) {
  12         var result, numbers;
  13         if (!arguments.length) return 0;
  14         some.call(arguments, function (val) {
  15                 if (isNaN(val)) {
  16                         result = NaN;
  17                         return;
  18                 }
  19                 if (!isFinite(val)) {
  20                         result = Infinity;
  21                         return true;
  22                 }
  23                 if (result !== undefined) return;
  24                 val = Number(val);
  25                 if (val === 0) return;
  26                 if (!numbers) numbers = [abs(val)];
  27                 else numbers.push(abs(val));
  28         });
  29         if (result !== undefined) return result;
  30         if (!numbers) return 0;
  31
  32         numbers.sort(compare);
  33         return numbers[0] * sqrt(numbers.map(divide, numbers[0]).reduce(add, 0));
  34 };