'Check a expovariate()-like function.  Note the second argument
is inversed compared to np.random.exponential().'

def _check_expovariate(self, func, ptr):

    r = self._follow_numpy(ptr)
    for lambd in (0.2, 0.5, 1.5):
        for i in range(3):
            self.assertPreciseEqual(func(lambd), r.exponential((1 / lambd)), prec='double')
