utils.py 文件源码

def extend_limits(values, fraction=0.10, tolerance=1e-2):
    """ Extend the values of a list by a fractional amount """

    values = np.array(values)
    finite_indices = np.isfinite(values)

    if np.sum(finite_indices) == 0:
        raise ValueError("no finite values provided")

    lower_limit, upper_limit = np.min(values[finite_indices]), np.max(values[finite_indices])
    ptp_value = np.ptp([lower_limit, upper_limit])

    new_limits = lower_limit - fraction * ptp_value, ptp_value * fraction + upper_limit

    if np.abs(new_limits[0] - new_limits[1]) < tolerance:
        if np.abs(new_limits[0]) < tolerance:
            # Arbitrary limits, since we"ve just been passed zeros
            offset = 1

        else:
            offset = np.abs(new_limits[0]) * fraction

        new_limits = new_limits[0] - offset, offset + new_limits[0]

    return np.array(new_limits)