manifold/common/util/math.ts

export const logInterpolation = (min: number, max: number, value: number) => {
  if (value <= min) return 0
  if (value >= max) return 1

  return Math.log(value - min + 1) / Math.log(max - min + 1)
}

export function normpdf(x: number, mean = 0, variance = 1) {
  if (variance === 0) {
    return x === mean ? Infinity : 0
  }

  return (
    Math.exp((-0.5 * Math.pow(x - mean, 2)) / variance) /
    Math.sqrt(TAU * variance)
  )
}

const TAU = Math.PI * 2