def boundCreator(mus, sigmas, c=3):
    """
    Creates interval around the mean

    Parameters
    ----------
    mus : array of shape [Num flights, time-steps, num of features]
        the mean temporal values to be used.
    sigmas : array of shape [Num flights, time-steps, num of features]
        the temporal standard deviation values to be used.
    c : TYPE, optional
        DESCRIPTION. The default is 3.

    Returns
    -------
    upper : array
        upper bound.
    lower : array
        lower bound.

    """
    upper = mus + c*sigmas
    lower = mus - c*sigmas
    return upper,lower