def calc_padding_lengths1D(length, length_padded):
    """
    Compute the padding lengths at both side along one dimension.

    Parameters
    ----------
    length: int
        Number of elements along one dimension of the original array
    length_padded: tuple
        Number of elements along one dimension of the padded array

    Returns
    -------
    pad_lengths: tuple
        A tuple under the form (padding_left, padding_right). These are the
        lengths needed to pad the original array.
    """
    pad_left = (length_padded - length) // 2
    pad_right = length_padded - length - pad_left
    return pad_left, pad_right
