test_utils.py 文件源码

def test_float64_pass(self):
        # The number of units of least precision
        # In this case, use a few places above the lowest level (ie nulp=1)
        nulp = 5
        x = np.linspace(-20, 20, 50, dtype=np.float64)
        x = 10**x
        x = np.r_[-x, x]

        # Addition
        eps = np.finfo(x.dtype).eps
        y = x + x*eps*nulp/2.
        assert_array_almost_equal_nulp(x, y, nulp)

        # Subtraction
        epsneg = np.finfo(x.dtype).epsneg
        y = x - x*epsneg*nulp/2.
        assert_array_almost_equal_nulp(x, y, nulp)