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# pylint: disable=invalid-name, trailing-whitespace
"""Softmax and log_softmax operation in python"""

import numpy as np


def softmax_python(a_np, axis=1):
    """Softmax operator.
    Parameters
    ----------
    a_np : numpy.ndarray
        N-D input data

    Returns
    -------
    output_np : numpy.ndarray
        N-D output with same shape
    """
    max_elem = np.amax(a_np, axis=axis, keepdims=True)
    e = np.exp(a_np - max_elem)
    expsum = np.sum(e, axis=axis, keepdims=True)
    out_np = e / expsum
    return out_np


def log_softmax_python(a_np, axis=1):
    """Log_softmax operator.
    Parameters
    ----------
    a_np : numpy.ndarray
        N-D input data

    Returns
    -------
    output_np : numpy.ndarray
        N-D output with same shape
    """
    max_elem = np.amax(a_np, axis=axis, keepdims=True)
    e = np.exp(a_np - max_elem)
    expsum = np.sum(e, axis=axis, keepdims=True)
    out_np = a_np - max_elem - np.log(expsum)
    return out_np