def retreive_filename(path):
    """
    Truncates absolute file directory and returns file name.

    Parameters
    ----------
    path : 1-dimensional string containing absolute directory of a file,
    in /<dir>/<filename>.<foramt> format.

    Returns
    -------
    filename : <filename> portion of the given file directory.
    """

    token = path.split('/')
    filename = token[-1].split('.')[0]

    return filename