"""Scalar float clipping with NumPy fallback for all other cases."""

import math

import numpy as np


def clip_scalar(value, lower, upper):
  if ((type(value) is float or type(value) is np.float64) and
      (type(lower) is float or type(lower) is np.float64) and
      (type(upper) is float or type(upper) is np.float64)):
    scalar, lo, hi = float(value), float(lower), float(upper)
    if (math.isfinite(scalar) and math.isfinite(lo) and math.isfinite(hi) and
        lo < hi and scalar != lo and scalar != hi):
      return lo if scalar < lo else hi if scalar > hi else scalar
  return float(np.clip(value, lower, upper))


def clip_float64(value, lower, upper):
  """Preserve NumPy's scalar result type while avoiding its scalar dispatch."""
  if ((type(value) is float or type(value) is np.float64) and
      (type(lower) is float or type(lower) is np.float64) and
      (type(upper) is float or type(upper) is np.float64)):
    return np.float64(clip_scalar(value, lower, upper))
  return np.clip(value, lower, upper)