Random walk gaussian

index.js

const R = require('ramda')
const plot = require('plotter').plot

const randomBoolean = () => Math.random() > 0.5
const randomOneOrMinusOne = () => randomBoolean() ? 1 : -1
const randomWalk = (length) => R.times(randomOneOrMinusOne, 100)
const randomWalkEnd = (length) => R.sum(randomWalk(length))
const manyRandomWalks = R.times(() => randomWalkEnd(100), 1000000)
const distribution = R.countBy(R.identity, manyRandomWalks)
const values = R.map((x) => distribution[x], R.range(-100, 100))

plot({
  data: values,
  filename: 'output.png'
})