def output_size(W, F, P, S):
    """
    https://adventuresinmachinelearning.com/convolutional-neural-networks-tutorial-in-pytorch/
    :param W: width in
    :param F: filter diameter
    :param P: padding
    :param S: stride
    :return:width out
    """
    return (W-F+2*P)/S + 1