def _compute_std_0(self, c1, c2, mag):
        """
        Common part of equations 27 and 28, pag 82.
        """
        if mag < 5:
            return c1
        elif mag >= 5 and mag <= 7:
            return c1 + (c2 - c1) * (mag - 5) / 2
        else:
            return c2
def _compute_std_0 ( self , c1 , c2 , mag ) : if mag < 5 : return c1 elif mag >= 5 and mag <= 7 : return c1 + ( c2 - c1 ) * ( mag - 5 ) / 2 else : return c2
Common part of equations 27 and 28, pag 82.