Function quantileIndex

src/quantile.js:35–47

(values, p, valueof = number)

}

export function quantileIndex(values, p, valueof = number) {
  if (isNaN(p = +p)) return;
  numbers = Float64Array.from(values, (_, i) => number(valueof(values[i], i, values)));
  if (p <= 0) return minIndex(numbers);
  if (p >= 1) return maxIndex(numbers);
  var numbers,
      index = Uint32Array.from(values, (_, i) => i),
      j = numbers.length - 1,
      i = Math.floor(j * p);
  quickselect(index, i, 0, j, (i, j) => ascendingDefined(numbers[i], numbers[j]));
  i = greatest(index.subarray(0, i + 1), (i) => numbers[i]);
  return i >= 0 ? i : -1;
}