File size: 7,766 Bytes
7885a28
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
import math
import numpy as np

from scipy._lib._array_api import (
    xp_assert_equal,
    assert_array_almost_equal,
    assert_almost_equal,
    is_cupy,
)

import pytest

from scipy import ndimage

from scipy.conftest import array_api_compatible
skip_xp_backends = pytest.mark.skip_xp_backends
pytestmark = [array_api_compatible, pytest.mark.usefixtures("skip_xp_backends"),
              skip_xp_backends(cpu_only=True, exceptions=['cupy', 'jax.numpy'],)]


@skip_xp_backends('jax.numpy', reason="jax-ml/jax#23827")
class TestNdimageFourier:

    @pytest.mark.parametrize('shape', [(32, 16), (31, 15), (1, 10)])
    @pytest.mark.parametrize('dtype, dec', [("float32", 6), ("float64", 14)])
    def test_fourier_gaussian_real01(self, shape, dtype, dec, xp):
        fft = getattr(xp, 'fft')

        a = np.zeros(shape, dtype=dtype)
        a[0, 0] = 1.0
        a = xp.asarray(a)

        a = fft.rfft(a, n=shape[0], axis=0)
        a = fft.fft(a, n=shape[1], axis=1)
        a = ndimage.fourier_gaussian(a, [5.0, 2.5], shape[0], 0)
        a = fft.ifft(a, n=shape[1], axis=1)
        a = fft.irfft(a, n=shape[0], axis=0)
        assert_almost_equal(ndimage.sum(a), xp.asarray(1), decimal=dec,
                            check_0d=False)

    @pytest.mark.parametrize('shape', [(32, 16), (31, 15)])
    @pytest.mark.parametrize('dtype, dec', [("complex64", 6), ("complex128", 14)])
    def test_fourier_gaussian_complex01(self, shape, dtype, dec, xp):
        fft = getattr(xp, 'fft')

        a = np.zeros(shape, dtype=dtype)
        a[0, 0] = 1.0
        a = xp.asarray(a)

        a = fft.fft(a, n=shape[0], axis=0)
        a = fft.fft(a, n=shape[1], axis=1)
        a = ndimage.fourier_gaussian(a, [5.0, 2.5], -1, 0)
        a = fft.ifft(a, n=shape[1], axis=1)
        a = fft.ifft(a, n=shape[0], axis=0)
        assert_almost_equal(ndimage.sum(xp.real(a)), xp.asarray(1.0), decimal=dec,
                            check_0d=False)

    @pytest.mark.parametrize('shape', [(32, 16), (31, 15), (1, 10)])
    @pytest.mark.parametrize('dtype, dec', [("float32", 6), ("float64", 14)])
    def test_fourier_uniform_real01(self, shape, dtype, dec, xp):
        fft = getattr(xp, 'fft')

        a = np.zeros(shape, dtype=dtype)
        a[0, 0] = 1.0
        a = xp.asarray(a)

        a = fft.rfft(a, n=shape[0], axis=0)
        a = fft.fft(a, n=shape[1], axis=1)
        a = ndimage.fourier_uniform(a, [5.0, 2.5], shape[0], 0)
        a = fft.ifft(a, n=shape[1], axis=1)
        a = fft.irfft(a, n=shape[0], axis=0)
        assert_almost_equal(ndimage.sum(a), xp.asarray(1.0), decimal=dec,
                            check_0d=False)

    @pytest.mark.parametrize('shape', [(32, 16), (31, 15)])
    @pytest.mark.parametrize('dtype, dec', [("complex64", 6), ("complex128", 14)])
    def test_fourier_uniform_complex01(self, shape, dtype, dec, xp):
        fft = getattr(xp, 'fft')

        a = np.zeros(shape, dtype=dtype)
        a[0, 0] = 1.0
        a = xp.asarray(a)

        a = fft.fft(a, n=shape[0], axis=0)
        a = fft.fft(a, n=shape[1], axis=1)
        a = ndimage.fourier_uniform(a, [5.0, 2.5], -1, 0)
        a = fft.ifft(a, n=shape[1], axis=1)
        a = fft.ifft(a, n=shape[0], axis=0)
        assert_almost_equal(ndimage.sum(xp.real(a)), xp.asarray(1.0), decimal=dec,
                            check_0d=False)

    @pytest.mark.parametrize('shape', [(32, 16), (31, 15)])
    @pytest.mark.parametrize('dtype, dec', [("float32", 4), ("float64", 11)])
    def test_fourier_shift_real01(self, shape, dtype, dec, xp):
        fft = getattr(xp, 'fft')

        expected = np.arange(shape[0] * shape[1], dtype=dtype).reshape(shape)
        expected = xp.asarray(expected)

        a = fft.rfft(expected, n=shape[0], axis=0)
        a = fft.fft(a, n=shape[1], axis=1)
        a = ndimage.fourier_shift(a, [1, 1], shape[0], 0)
        a = fft.ifft(a, n=shape[1], axis=1)
        a = fft.irfft(a, n=shape[0], axis=0)
        assert_array_almost_equal(a[1:, 1:], expected[:-1, :-1], decimal=dec)

    @pytest.mark.parametrize('shape', [(32, 16), (31, 15)])
    @pytest.mark.parametrize('dtype, dec', [("complex64", 4), ("complex128", 11)])
    def test_fourier_shift_complex01(self, shape, dtype, dec, xp):
        fft = getattr(xp, 'fft')

        expected = np.arange(shape[0] * shape[1], dtype=dtype).reshape(shape)
        expected = xp.asarray(expected)

        a = fft.fft(expected, n=shape[0], axis=0)
        a = fft.fft(a, n=shape[1], axis=1)
        a = ndimage.fourier_shift(a, [1, 1], -1, 0)
        a = fft.ifft(a, n=shape[1], axis=1)
        a = fft.ifft(a, n=shape[0], axis=0)
        assert_array_almost_equal(xp.real(a)[1:, 1:], expected[:-1, :-1], decimal=dec)
        assert_array_almost_equal(xp.imag(a), xp.zeros(shape), decimal=dec)

    @pytest.mark.parametrize('shape', [(32, 16), (31, 15), (1, 10)])
    @pytest.mark.parametrize('dtype, dec', [("float32", 5), ("float64", 14)])
    def test_fourier_ellipsoid_real01(self, shape, dtype, dec, xp):
        fft = getattr(xp, 'fft')

        a = np.zeros(shape, dtype=dtype)
        a[0, 0] = 1.0
        a = xp.asarray(a)

        a = fft.rfft(a, n=shape[0], axis=0)
        a = fft.fft(a, n=shape[1], axis=1)
        a = ndimage.fourier_ellipsoid(a, [5.0, 2.5], shape[0], 0)
        a = fft.ifft(a, n=shape[1], axis=1)
        a = fft.irfft(a, n=shape[0], axis=0)
        assert_almost_equal(ndimage.sum(a), xp.asarray(1.0), decimal=dec,
                            check_0d=False)

    @pytest.mark.parametrize('shape', [(32, 16), (31, 15)])
    @pytest.mark.parametrize('dtype, dec', [("complex64", 5), ("complex128", 14)])
    def test_fourier_ellipsoid_complex01(self, shape, dtype, dec, xp):
        fft = getattr(xp, 'fft')

        a = np.zeros(shape, dtype=dtype)
        a[0, 0] = 1.0
        a = xp.asarray(a)

        a = fft.fft(a, n=shape[0], axis=0)
        a = fft.fft(a, n=shape[1], axis=1)
        a = ndimage.fourier_ellipsoid(a, [5.0, 2.5], -1, 0)
        a = fft.ifft(a, n=shape[1], axis=1)
        a = fft.ifft(a, n=shape[0], axis=0)
        assert_almost_equal(ndimage.sum(xp.real(a)), xp.asarray(1.0), decimal=dec,
                            check_0d=False)

    def test_fourier_ellipsoid_unimplemented_ndim(self, xp):
        # arrays with ndim > 3 raise NotImplementedError
        x = xp.ones((4, 6, 8, 10), dtype=xp.complex128)
        with pytest.raises(NotImplementedError):
            ndimage.fourier_ellipsoid(x, 3)

    def test_fourier_ellipsoid_1d_complex(self, xp):
        # expected result of 1d ellipsoid is the same as for fourier_uniform
        for shape in [(32, ), (31, )]:
            for type_, dec in zip([xp.complex64, xp.complex128], [5, 14]):
                x = xp.ones(shape, dtype=type_)
                a = ndimage.fourier_ellipsoid(x, 5, -1, 0)
                b = ndimage.fourier_uniform(x, 5, -1, 0)
                assert_array_almost_equal(a, b, decimal=dec)

    @pytest.mark.parametrize('shape', [(0, ), (0, 10), (10, 0)])
    @pytest.mark.parametrize('dtype', ["float32", "float64",
                                       "complex64", "complex128"])
    @pytest.mark.parametrize('test_func',
                             [ndimage.fourier_ellipsoid,
                              ndimage.fourier_gaussian,
                              ndimage.fourier_uniform])
    def test_fourier_zero_length_dims(self, shape, dtype, test_func, xp):
        if is_cupy(xp):
           if (test_func.__name__ == "fourier_ellipsoid" and
               math.prod(shape) == 0):
               pytest.xfail(
                   "CuPy's fourier_ellipsoid does not accept size==0 arrays"
               )
        dtype = getattr(xp, dtype)
        a = xp.ones(shape, dtype=dtype)
        b = test_func(a, 3)
        xp_assert_equal(a, b)