def get_stack_freq(path):
    """
    Get the temporal data from the Stack_frequency.txt file found in
    path. Return volumetric sampling rate in Hz,
    total recording length in seconds, and total number
    of volumes in a tuple.
    """
    f = open(path + "Stack_frequency.txt")
    times = [float(line) for line in f]

    # third value should be an integer
    times[2] = int(times[2])

    return times