Function reducedRational

src/compute-engine/numerics/rationals.ts:237–262

(r: Rational)

export function reducedRational(r: [bigint, bigint]): [bigint, bigint];
export function reducedRational(r: Rational): Rational;
export function reducedRational(r: Rational): Rational {
  if (isMachineRational(r)) {
    // Normalize negative denominator first (before early return)
    if (r[1] < 0) r = [-r[0], -r[1]];
    if (r[0] === 1 || r[1] === 1) return r;
    if (!Number.isFinite(r[1])) return [0, 1];
    const g = gcd(r[0], r[1]);
    //  If the gcd is 0, return the rational unchanged
    return g <= 1 ? r : [r[0] / g, r[1] / g];
  }

  if (r[1] < 0) r = [-r[0], -r[1]];

  const g = bigGcd(r[0], r[1]);

  //  If the gcd is 0, return the rational unchanged
  const [n, d] = g <= 1 ? r : [r[0] / g, r[1] / g];

  if (
    n <= Number.MAX_SAFE_INTEGER &&
    n >= Number.MIN_SAFE_INTEGER &&
    d <= Number.MAX_SAFE_INTEGER
  )
    return [Number(n), Number(d)];
  return [n, d];
}

/**
 * Return `value / denom` as an exact reduced machine rational, or `null` if