test_half.py 文件源码

def test_half_rounding(self):
        """Checks that rounding when converting to half is correct"""
        a = np.array([2.0**-25 + 2.0**-35,  # Rounds to minimum subnormal
                      2.0**-25,       # Underflows to zero (nearest even mode)
                      2.0**-26,       # Underflows to zero
                      1.0+2.0**-11 + 2.0**-16,  # rounds to 1.0+2**(-10)
                      1.0+2.0**-11,   # rounds to 1.0 (nearest even mode)
                      1.0+2.0**-12,   # rounds to 1.0
                      65519,          # rounds to 65504
                      65520],         # rounds to inf
                      dtype=float64)
        rounded = [2.0**-24,
                   0.0,
                   0.0,
                   1.0+2.0**(-10),
                   1.0,
                   1.0,
                   65504,
                   np.inf]

        # Check float64->float16 rounding
        b = np.array(a, dtype=float16)
        assert_equal(b, rounded)

        # Check float32->float16 rounding
        a = np.array(a, dtype=float32)
        b = np.array(a, dtype=float16)
        assert_equal(b, rounded)