@thi.ng/colored-noise/blue.js

Customizable O(1) ES6 generators for colored noise

import { DEFAULT_OPTS } from "./api.js";
import { preseed, sum } from "./utils.js";
function* blue(opts) {
  const { bins, scale, rnd } = { ...DEFAULT_OPTS, ...opts };
  const state = preseed(bins, scale, rnd);
  state.forEach((x, i) => state[i] = i & 1 ? x : -x);
  const invN = 1 / bins;
  let acc = sum(state);
  for (let i = 0, sign = -1; true; ++i >= bins && (i = 0)) {
    acc -= state[i];
    acc += state[i] = sign * rnd.norm(scale);
    sign ^= 4294967294;
    yield sign * acc * invN;
  }
}
export {
  blue
};