def convert_np_to_float16()

in scripts/float16.py [0:0]

• 48 lines of code
• 7 McCabe index (conditional complexity)

def convert_np_to_float16(np_array, min_positive_val=1e-7, max_finite_val=1e4):
    """
    Convert float32 numpy array to float16 without changing sign or finiteness.
    Positive values less than min_positive_val are mapped to min_positive_val.
    Positive finite values greater than max_finite_val are mapped to max_finite_val.
    Similar for negative values. NaN, 0, inf, and -inf are unchanged.
    """

    def between(a, b, c):
        return np.logical_and(a < b, b < c)

    positive_values = np_array[np.where(np_array > 0)]
    if positive_values.shape[0] > 0:
        pos_max = positive_values.max()
        pos_min = positive_values.min()

        if pos_max >= max_finite_val:
            warnings.warn(
                "the float32 number {} will be truncated to {}".format(
                    pos_max, max_finite_val
                )
            )

        if pos_min <= min_positive_val:
            warnings.warn(
                "the float32 number {} will be truncated to {}".format(
                    pos_min, min_positive_val
                )
            )

    negative_values = np_array[np.where(np_array < 0)]
    if negative_values.shape[0] > 0:
        neg_max = negative_values.max()
        neg_min = negative_values.min()

        if neg_min <= -max_finite_val:
            warnings.warn(
                "the float32 number {} will be truncated to {}".format(
                    neg_min, -max_finite_val
                )
            )

        if neg_max >= -min_positive_val:
            warnings.warn(
                "the float32 number {} will be truncated to {}".format(
                    neg_max, -min_positive_val
                )
            )

    np_array = np.where(
        between(0, np_array, min_positive_val), min_positive_val, np_array
    )
    np_array = np.where(
        between(-min_positive_val, np_array, 0), -min_positive_val, np_array
    )
    np_array = np.where(
        between(max_finite_val, np_array, float("inf")), max_finite_val, np_array
    )
    np_array = np.where(
        between(float("-inf"), np_array, -max_finite_val), -max_finite_val, np_array
    )
    return np.float16(np_array)