def METHOD_NAME(self, size, n):
    bm.use_cpu()
    s = np.random.randn(size)
    res = bm.rfft(s, n=n)
    bm.use_gpu()
    s_gpu = self.cp.array(s)
    res_gpu = bm.rfft(s_gpu, n=n)
    self.cp.testing.assert_array_almost_equal(res_gpu, res, decimal=8)