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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def rhypo_to_rjb(rhypo, mag):
 """ Converts hypocentral distance to an equivalent Joyner-Boore distance dependent on the magnitude """

    epsilon = rhypo - (4.853 + 1.347E-6 * (mag ** 8.163))
    rjb = np.zeros_like(rhypo)
    idx = epsilon >= 3.
    rjb[idx] = np.sqrt((epsilon[idx] ** 2.) - 9.0)
    rjb[rjb < 0.0] = 0.0
    return rjb