def energy_calc(edot, t_int):
    """
    Calculates magnetar giant flare energy for a given flare interval,
    based on the energy injection rate and a flare interval (directly
    from the magnetar's age).

    Args:
    - edot: Energy injection rate at a specific age
    - t_int: Flare interval at a given age

    Returns:
    - e_f: Flare energy for a given E-dot and flare interval at a specific
     age
    """
    e_f = edot * t_int  # As E-dot is defined as e_f/t_int
    return e_f