Python numpy 模块，NZERO 实例源码

我们从Python开源项目中，提取了以下50个代码示例，用于说明如何使用numpy.NZERO。

项目：radar 作者：amoose136 | 项目源码 | 文件源码

def test_zero_nzero(self):
        # atan2(+-0, -0) returns +-pi.
        assert_almost_equal(ncu.arctan2(np.PZERO, np.NZERO), np.pi)
        assert_almost_equal(ncu.arctan2(np.NZERO, np.NZERO), -np.pi)

项目：radar 作者：amoose136 | 项目源码 | 文件源码

def test_zero_pzero(self):
        # atan2(+-0, +0) returns +-0.
        assert_arctan2_ispzero(np.PZERO, np.PZERO)
        assert_arctan2_isnzero(np.NZERO, np.PZERO)

项目：radar 作者：amoose136 | 项目源码 | 文件源码

def test_zero_negative(self):
        # atan2(+-0, x) returns +-pi for x < 0.
        assert_almost_equal(ncu.arctan2(np.PZERO, -1), np.pi)
        assert_almost_equal(ncu.arctan2(np.NZERO, -1), -np.pi)

项目：radar 作者：amoose136 | 项目源码 | 文件源码

def test_zero_positive(self):
        # atan2(+-0, x) returns +-0 for x > 0.
        assert_arctan2_ispzero(np.PZERO, 1)
        assert_arctan2_isnzero(np.NZERO, 1)

项目：radar 作者：amoose136 | 项目源码 | 文件源码

def test_positive_zero(self):
        # atan2(y, +-0) returns +pi/2 for y > 0.
        assert_almost_equal(ncu.arctan2(1, np.PZERO), 0.5 * np.pi)
        assert_almost_equal(ncu.arctan2(1, np.NZERO), 0.5 * np.pi)

项目：radar 作者：amoose136 | 项目源码 | 文件源码

def test_fabs(self):
        # Test that np.abs(x +- 0j) == np.abs(x) (as mandated by C99 for cabs)
        x = np.array([1+0j], dtype=np.complex)
        assert_array_equal(np.abs(x), np.real(x))

        x = np.array([complex(1, np.NZERO)], dtype=np.complex)
        assert_array_equal(np.abs(x), np.real(x))

        x = np.array([complex(np.inf, np.NZERO)], dtype=np.complex)
        assert_array_equal(np.abs(x), np.real(x))

        x = np.array([complex(np.nan, np.NZERO)], dtype=np.complex)
        assert_array_equal(np.abs(x), np.real(x))

项目：radar 作者：amoose136 | 项目源码 | 文件源码

def test_zero(self):
        # carg(-0 +- 0i) returns +- pi
        yield check_real_value, ncu._arg, np.NZERO, np.PZERO,  np.pi, False
        yield check_real_value, ncu._arg, np.NZERO, np.NZERO, -np.pi, False

        # carg(+0 +- 0i) returns +- 0
        yield check_real_value, ncu._arg, np.PZERO, np.PZERO, np.PZERO
        yield check_real_value, ncu._arg, np.PZERO, np.NZERO, np.NZERO

        # carg(x +- 0i) returns +- 0 for x > 0
        yield check_real_value, ncu._arg, 1, np.PZERO, np.PZERO, False
        yield check_real_value, ncu._arg, 1, np.NZERO, np.NZERO, False

        # carg(x +- 0i) returns +- pi for x < 0
        yield check_real_value, ncu._arg, -1, np.PZERO,  np.pi, False
        yield check_real_value, ncu._arg, -1, np.NZERO, -np.pi, False

        # carg(+- 0 + yi) returns pi/2 for y > 0
        yield check_real_value, ncu._arg, np.PZERO, 1, 0.5 * np.pi, False
        yield check_real_value, ncu._arg, np.NZERO, 1, 0.5 * np.pi, False

        # carg(+- 0 + yi) returns -pi/2 for y < 0
        yield check_real_value, ncu._arg, np.PZERO, -1, 0.5 * np.pi, False
        yield check_real_value, ncu._arg, np.NZERO, -1, -0.5 * np.pi, False

    #def test_branch_cuts(self):
    #    _check_branch_cut(ncu._arg, -1, 1j, -1, 1)

项目：radar 作者：amoose136 | 项目源码 | 文件源码

def test_special_values(self):
        # carg(-np.inf +- yi) returns +-pi for finite y > 0
        yield check_real_value, ncu._arg, -np.inf,  1,  np.pi, False
        yield check_real_value, ncu._arg, -np.inf, -1, -np.pi, False

        # carg(np.inf +- yi) returns +-0 for finite y > 0
        yield check_real_value, ncu._arg, np.inf,  1, np.PZERO, False
        yield check_real_value, ncu._arg, np.inf, -1, np.NZERO, False

        # carg(x +- np.infi) returns +-pi/2 for finite x
        yield check_real_value, ncu._arg, 1,  np.inf,  0.5 * np.pi, False
        yield check_real_value, ncu._arg, 1, -np.inf, -0.5 * np.pi, False

        # carg(-np.inf +- np.infi) returns +-3pi/4
        yield check_real_value, ncu._arg, -np.inf,  np.inf,  0.75 * np.pi, False
        yield check_real_value, ncu._arg, -np.inf, -np.inf, -0.75 * np.pi, False

        # carg(np.inf +- np.infi) returns +-pi/4
        yield check_real_value, ncu._arg, np.inf,  np.inf,  0.25 * np.pi, False
        yield check_real_value, ncu._arg, np.inf, -np.inf, -0.25 * np.pi, False

        # carg(x + yi) returns np.nan if x or y is nan
        yield check_real_value, ncu._arg, np.nan,      0, np.nan, False
        yield check_real_value, ncu._arg,      0, np.nan, np.nan, False

        yield check_real_value, ncu._arg, np.nan, np.inf, np.nan, False
        yield check_real_value, ncu._arg, np.inf, np.nan, np.nan, False

项目：radar 作者：amoose136 | 项目源码 | 文件源码

def test_nan(self):
        # Test that nan is 'far' from small, tiny, inf, max and min
        for dt in [np.float32, np.float64]:
            if dt == np.float32:
                maxulp = 1e6
            else:
                maxulp = 1e12
            inf = np.array([np.inf]).astype(dt)
            nan = np.array([np.nan]).astype(dt)
            big = np.array([np.finfo(dt).max])
            tiny = np.array([np.finfo(dt).tiny])
            zero = np.array([np.PZERO]).astype(dt)
            nzero = np.array([np.NZERO]).astype(dt)
            self.assertRaises(AssertionError,
                                  lambda: assert_array_max_ulp(nan, inf,
                                                               maxulp=maxulp))
            self.assertRaises(AssertionError,
                                  lambda: assert_array_max_ulp(nan, big,
                                                               maxulp=maxulp))
            self.assertRaises(AssertionError,
                                  lambda: assert_array_max_ulp(nan, tiny,
                                                               maxulp=maxulp))
            self.assertRaises(AssertionError,
                                  lambda: assert_array_max_ulp(nan, zero,
                                                               maxulp=maxulp))
            self.assertRaises(AssertionError,
                                  lambda: assert_array_max_ulp(nan, nzero,
                                                               maxulp=maxulp))