def get_sim_time_span(n_interval, step_size):
    """Calculate the time span of the simulation.

    :param n_interval: number of intervals
    :type n_interval: integer
    :step_size: length of one time step in minutes
    :type step_size: number
    :return: time delta in minutes
    :rtype: number
    """
    return n_interval * step_size