d3-random/src/irwinHall.js

Generate random numbers from various distributions.

import defaultSource from "./defaultSource.js";

export default (function sourceRandomIrwinHall(source) {
  function randomIrwinHall(n) {
    if ((n = +n) <= 0) return () => 0;
    return function() {
      for (var sum = 0, i = n; i > 1; --i) sum += source();
      return sum + i * source();
    };
  }

  randomIrwinHall.source = sourceRandomIrwinHall;

  return randomIrwinHall;
})(defaultSource);