import numpy as np
import pytest
from numpy.random import random
from numpy.testing import (
assert_array_equal, assert_raises, assert_allclose, IS_WASM
)
import threading
import queue
def fft1(x):
L = len(x)
phase = -2j * np.pi * (np.arange(L) / L)
phase = np.arange(L).reshape(-1, 1) * phase
return np.sum(x*np.exp(phase), axis=1)
class TestFFTShift:
def test_fft_n(self):
assert_raises(ValueError, np.fft.fft, [1, 2, 3], 0)
class TestFFT1D:
def test_identity(self):
maxlen = 512
x = random(maxlen) + 1j*random(maxlen)
xr = random(maxlen)
for i in range(1, maxlen):
assert_allclose(np.fft.ifft(np.fft.fft(x[0:i])), x[0:i],
atol=1e-12)
assert_allclose(np.fft.irfft(np.fft.rfft(xr[0:i]), i),
xr[0:i], atol=1e-12)
@pytest.mark.parametrize("dtype", [np.single, np.double, np.longdouble])
def test_identity_long_short(self, dtype):
# Test with explicitly given number of points, both for n
# smaller and for n larger than the input size.
maxlen = 16
atol = 5 * np.spacing(np.array(1., dtype=dtype))
x = random(maxlen).astype(dtype) + 1j*random(maxlen).astype(dtype)
xx = np.concatenate([x, np.zeros_like(x)])
xr = random(maxlen).astype(dtype)
xxr = np.concatenate([xr, np.zeros_like(xr)])
for i in range(1, maxlen*2):
check_c = np.fft.ifft(np.fft.fft(x, n=i), n=i)
assert check_c.real.dtype == dtype
assert_allclose(check_c, xx[0:i], atol=atol, rtol=0)
check_r = np.fft.irfft(np.fft.rfft(xr, n=i), n=i)
assert check_r.dtype == dtype
assert_allclose(check_r, xxr[0:i], atol=atol, rtol=0)
@pytest.mark.parametrize("dtype", [np.single, np.double, np.longdouble])
def test_identity_long_short_reversed(self, dtype):
# Also test explicitly given number of points in reversed order.
maxlen = 16
atol = 5 * np.spacing(np.array(1., dtype=dtype))
x = random(maxlen).astype(dtype) + 1j*random(maxlen).astype(dtype)
xx = np.concatenate([x, np.zeros_like(x)])
for i in range(1, maxlen*2):
check_via_c = np.fft.fft(np.fft.ifft(x, n=i), n=i)
assert check_via_c.dtype == x.dtype
assert_allclose(check_via_c, xx[0:i], atol=atol, rtol=0)
# For irfft, we can neither recover the imaginary part of
# the first element, nor the imaginary part of the last
# element if npts is even. So, set to 0 for the comparison.
y = x.copy()
n = i // 2 + 1
y.imag[0] = 0
if i % 2 == 0:
y.imag[n-1:] = 0
yy = np.concatenate([y, np.zeros_like(y)])
check_via_r = np.fft.rfft(np.fft.irfft(x, n=i), n=i)
assert check_via_r.dtype == x.dtype
assert_allclose(check_via_r, yy[0:n], atol=atol, rtol=0)
def test_fft(self):
x = random(30) + 1j*random(30)
assert_allclose(fft1(x), np.fft.fft(x), atol=1e-6)
assert_allclose(fft1(x), np.fft.fft(x, norm="backward"), atol=1e-6)
assert_allclose(fft1(x) / np.sqrt(30),
np.fft.fft(x, norm="ortho"), atol=1e-6)
assert_allclose(fft1(x) / 30.,
np.fft.fft(x, norm="forward"), atol=1e-6)
@pytest.mark.parametrize("axis", (0, 1))
@pytest.mark.parametrize("dtype", (complex, float))
@pytest.mark.parametrize("transpose", (True, False))
def test_fft_out_argument(self, dtype, transpose, axis):
def zeros_like(x):
if transpose:
return np.zeros_like(x.T).T
else:
return np.zeros_like(x)
# tests below only test the out parameter
if dtype is complex:
y = random((10, 20)) + 1j*random((10, 20))
fft, ifft = np.fft.fft, np.fft.ifft
else:
y = random((10, 20))
fft, ifft = np.fft.rfft, np.fft.irfft
expected = fft(y, axis=axis)
out = zeros_like(expected)
result = fft(y, out=out, axis=axis)
assert result is out
assert_array_equal(result, expected)
expected2 = ifft(expected, axis=axis)
out2 = out if dtype is complex else zeros_like(expected2)
result2 = ifft(out, out=out2, axis=axis)
assert result2 is out2
assert_array_equal(result2, expected2)
@pytest.mark.parametrize("axis", [0, 1])
def test_fft_inplace_out(self, axis):
# Test some weirder in-place combinations
y = random((20, 20)) + 1j*random((20, 20))
# Fully in-place.
y1 = y.copy()
expected1 = np.fft.fft(y1, axis=axis)
result1 = np.fft.fft(y1, axis=axis, out=y1)
assert result1 is y1
assert_array_equal(result1, expected1)
# In-place of part of the array; rest should be unchanged.
y2 = y.copy()
out2 = y2[:10] if axis == 0 else y2[:, :10]
expected2 = np.fft.fft(y2, n=10, axis=axis)
result2 = np.fft.fft(y2, n=10, axis=axis, out=out2)
assert result2 is out2
assert_array_equal(result2, expected2)
if axis == 0:
assert_array_equal(y2[10:], y[10:])
else:
assert_array_equal(y2[:, 10:], y[:, 10:])
# In-place of another part of the array.
y3 = y.copy()
y3_sel = y3[5:] if axis == 0 else y3[:, 5:]
out3 = y3[5:15] if axis == 0 else y3[:, 5:15]
expected3 = np.fft.fft(y3_sel, n=10, axis=axis)
result3 = np.fft.fft(y3_sel, n=10, axis=axis, out=out3)
assert result3 is out3
assert_array_equal(result3, expected3)
if axis == 0:
assert_array_equal(y3[:5], y[:5])
assert_array_equal(y3[15:], y[15:])
else:
assert_array_equal(y3[:, :5], y[:, :5])
assert_array_equal(y3[:, 15:], y[:, 15:])
# In-place with n > nin; rest should be unchanged.
y4 = y.copy()
y4_sel = y4[:10] if axis == 0 else y4[:, :10]
out4 = y4[:15] if axis == 0 else y4[:, :15]
expected4 = np.fft.fft(y4_sel, n=15, axis=axis)
result4 = np.fft.fft(y4_sel, n=15, axis=axis, out=out4)
assert result4 is out4
assert_array_equal(result4, expected4)
if axis == 0:
assert_array_equal(y4[15:], y[15:])
else:
assert_array_equal(y4[:, 15:], y[:, 15:])
# Overwrite in a transpose.
y5 = y.copy()
out5 = y5.T
result5 = np.fft.fft(y5, axis=axis, out=out5)
assert result5 is out5
assert_array_equal(result5, expected1)
# Reverse strides.
y6 = y.copy()
out6 = y6[::-1] if axis == 0 else y6[:, ::-1]
result6 = np.fft.fft(y6, axis=axis, out=out6)
assert result6 is out6
assert_array_equal(result6, expected1)
def test_fft_bad_out(self):
x = np.arange(30.)
with pytest.raises(TypeError, match="must be of ArrayType"):
np.fft.fft(x, out="")
with pytest.raises(ValueError, match="has wrong shape"):
np.fft.fft(x, out=np.zeros_like(x).reshape(5, -1))
with pytest.raises(TypeError, match="Cannot cast"):
np.fft.fft(x, out=np.zeros_like(x, dtype=float))
@pytest.mark.parametrize('norm', (None, 'backward', 'ortho', 'forward'))
def test_ifft(self, norm):
x = random(30) + 1j*random(30)
assert_allclose(
x, np.fft.ifft(np.fft.fft(x, norm=norm), norm=norm),
atol=1e-6)
# Ensure we get the correct error message
with pytest.raises(ValueError,
match='Invalid number of FFT data points'):
np.fft.ifft([], norm=norm)
def test_fft2(self):
x = random((30, 20)) + 1j*random((30, 20))
assert_allclose(np.fft.fft(np.fft.fft(x, axis=1), axis=0),
np.fft.fft2(x), atol=1e-6)
assert_allclose(np.fft.fft2(x),
np.fft.fft2(x, norm="backward"), atol=1e-6)
assert_allclose(np.fft.fft2(x) / np.sqrt(30 * 20),
np.fft.fft2(x, norm="ortho"), atol=1e-6)
assert_allclose(np.fft.fft2(x) / (30. * 20.),
np.fft.fft2(x, norm="forward"), atol=1e-6)
def test_ifft2(self):
x = random((30, 20)) + 1j*random((30, 20))
assert_allclose(np.fft.ifft(np.fft.ifft(x, axis=1), axis=0),
np.fft.ifft2(x), atol=1e-6)
assert_allclose(np.fft.ifft2(x),
np.fft.ifft2(x, norm="backward"), atol=1e-6)
assert_allclose(np.fft.ifft2(x) * np.sqrt(30 * 20),
np.fft.ifft2(x, norm="ortho"), atol=1e-6)
assert_allclose(np.fft.ifft2(x) * (30. * 20.),
np.fft.ifft2(x, norm="forward"), atol=1e-6)
def test_fftn(self):
x = random((30, 20, 10)) + 1j*random((30, 20, 10))
assert_allclose(
np.fft.fft(np.fft.fft(np.fft.fft(x, axis=2), axis=1), axis=0),
np.fft.fftn(x), atol=1e-6)
assert_allclose(np.fft.fftn(x),
np.fft.fftn(x, norm="backward"), atol=1e-6)
assert_allclose(np.fft.fftn(x) / np.sqrt(30 * 20 * 10),
np.fft.fftn(x, norm="ortho"), atol=1e-6)
assert_allclose(np.fft.fftn(x) / (30. * 20. * 10.),
np.fft.fftn(x, norm="forward"), atol=1e-6)
def test_ifftn(self):
x = random((30, 20, 10)) + 1j*random((30, 20, 10))
assert_allclose(
np.fft.ifft(np.fft.ifft(np.fft.ifft(x, axis=2), axis=1), axis=0),
np.fft.ifftn(x), atol=1e-6)
assert_allclose(np.fft.ifftn(x),
np.fft.ifftn(x, norm="backward"), atol=1e-6)
assert_allclose(np.fft.ifftn(x) * np.sqrt(30 * 20 * 10),
np.fft.ifftn(x, norm="ortho"), atol=1e-6)
assert_allclose(np.fft.ifftn(x) * (30. * 20. * 10.),
np.fft.ifftn(x, norm="forward"), atol=1e-6)
def test_rfft(self):
x = random(30)
for n in [x.size, 2*x.size]:
for norm in [None, 'backward', 'ortho', 'forward']:
assert_allclose(
np.fft.fft(x, n=n, norm=norm)[:(n//2 + 1)],
np.fft.rfft(x, n=n, norm=norm), atol=1e-6)
assert_allclose(
np.fft.rfft(x, n=n),
np.fft.rfft(x, n=n, norm="backward"), atol=1e-6)
assert_allclose(
np.fft.rfft(x, n=n) / np.sqrt(n),
np.fft.rfft(x, n=n, norm="ortho"), atol=1e-6)
assert_allclose(
np.fft.rfft(x, n=n) / n,
np.fft.rfft(x, n=n, norm="forward"), atol=1e-6)
def test_rfft_even(self):
x = np.arange(8)
n = 4
y = np.fft.rfft(x, n)
assert_allclose(y, np.fft.fft(x[:n])[:n//2 + 1], rtol=1e-14)
def test_rfft_odd(self):
x = np.array([1, 0, 2, 3, -3])
y = np.fft.rfft(x)
assert_allclose(y, np.fft.fft(x)[:3], rtol=1e-14)
def test_irfft(self):
x = random(30)
assert_allclose(x, np.fft.irfft(np.fft.rfft(x)), atol=1e-6)
assert_allclose(x, np.fft.irfft(np.fft.rfft(x, norm="backward"),
norm="backward"), atol=1e-6)
assert_allclose(x, np.fft.irfft(np.fft.rfft(x, norm="ortho"),
norm="ortho"), atol=1e-6)
assert_allclose(x, np.fft.irfft(np.fft.rfft(x, norm="forward"),
norm="forward"), atol=1e-6)
def test_rfft2(self):
x = random((30, 20))
assert_allclose(np.fft.fft2(x)[:, :11], np.fft.rfft2(x), atol=1e-6)
assert_allclose(np.fft.rfft2(x),
np.fft.rfft2(x, norm="backward"), atol=1e-6)
assert_allclose(np.fft.rfft2(x) / np.sqrt(30 * 20),
np.fft.rfft2(x, norm="ortho"), atol=1e-6)
assert_allclose(np.fft.rfft2(x) / (30. * 20.),
np.fft.rfft2(x, norm="forward"), atol=1e-6)
def test_irfft2(self):
x = random((30, 20))
assert_allclose(x, np.fft.irfft2(np.fft.rfft2(x)), atol=1e-6)
assert_allclose(x, np.fft.irfft2(np.fft.rfft2(x, norm="backward"),
norm="backward"), atol=1e-6)
assert_allclose(x, np.fft.irfft2(np.fft.rfft2(x, norm="ortho"),
norm="ortho"), atol=1e-6)
assert_allclose(x, np.fft.irfft2(np.fft.rfft2(x, norm="forward"),
norm="forward"), atol=1e-6)
def test_rfftn(self):
x = random((30, 20, 10))
assert_allclose(np.fft.fftn(x)[:, :, :6], np.fft.rfftn(x), atol=1e-6)
assert_allclose(np.fft.rfftn(x),
np.fft.rfftn(x, norm="backward"), atol=1e-6)
assert_allclose(np.fft.rfftn(x) / np.sqrt(30 * 20 * 10),
np.fft.rfftn(x, norm="ortho"), atol=1e-6)
assert_allclose(np.fft.rfftn(x) / (30. * 20. * 10.),
np.fft.rfftn(x, norm="forward"), atol=1e-6)
# Regression test for gh-27159
x = np.ones((2, 3))
result = np.fft.rfftn(x, axes=(0, 0, 1), s=(10, 20, 40))
assert result.shape == (10, 21)
expected = np.fft.fft(np.fft.fft(np.fft.rfft(x, axis=1, n=40),
axis=0, n=20), axis=0, n=10)
assert expected.shape == (10, 21)
assert_allclose(result, expected, atol=1e-6)
def test_irfftn(self):
x = random((30, 20, 10))
assert_allclose(x, np.fft.irfftn(np.fft.rfftn(x)), atol=1e-6)
assert_allclose(x, np.fft.irfftn(np.fft.rfftn(x, norm="backward"),
norm="backward"), atol=1e-6)
assert_allclose(x, np.fft.irfftn(np.fft.rfftn(x, norm="ortho"),
norm="ortho"), atol=1e-6)
assert_allclose(x, np.fft.irfftn(np.fft.rfftn(x, norm="forward"),
norm="forward"), atol=1e-6)
def test_hfft(self):
x = random(14) + 1j*random(14)
x_herm = np.concatenate((random(1), x, random(1)))
x = np.concatenate((x_herm, x[::-1].conj()))
assert_allclose(np.fft.fft(x), np.fft.hfft(x_herm), atol=1e-6)
assert_allclose(np.fft.hfft(x_herm),
np.fft.hfft(x_herm, norm="backward"), atol=1e-6)
assert_allclose(np.fft.hfft(x_herm) / np.sqrt(30),
np.fft.hfft(x_herm, norm="ortho"), atol=1e-6)
assert_allclose(np.fft.hfft(x_herm) / 30.,
np.fft.hfft(x_herm, norm="forward"), atol=1e-6)
def test_ihfft(self):
x = random(14) + 1j*random(14)
x_herm = np.concatenate((random(1), x, random(1)))
x = np.concatenate((x_herm, x[::-1].conj()))
assert_allclose(x_herm, np.fft.ihfft(np.fft.hfft(x_herm)), atol=1e-6)
assert_allclose(x_herm, np.fft.ihfft(np.fft.hfft(x_herm,
norm="backward"), norm="backward"), atol=1e-6)
assert_allclose(x_herm, np.fft.ihfft(np.fft.hfft(x_herm,
norm="ortho"), norm="ortho"), atol=1e-6)
assert_allclose(x_herm, np.fft.ihfft(np.fft.hfft(x_herm,
norm="forward"), norm="forward"), atol=1e-6)
@pytest.mark.parametrize("op", [np.fft.fftn, np.fft.ifftn,
np.fft.rfftn, np.fft.irfftn])
def test_axes(self, op):
x = random((30, 20, 10))
axes = [(0, 1, 2), (0, 2, 1), (1, 0, 2), (1, 2, 0), (2, 0, 1), (2, 1, 0)]
for a in axes:
op_tr = op(np.transpose(x, a))
tr_op = np.transpose(op(x, axes=a), a)
assert_allclose(op_tr, tr_op, atol=1e-6)
@pytest.mark.parametrize("op", [np.fft.fftn, np.fft.ifftn,
np.fft.fft2, np.fft.ifft2])
def test_s_negative_1(self, op):
x = np.arange(100).reshape(10, 10)
# should use the whole input array along the first axis
assert op(x, s=(-1, 5), axes=(0, 1)).shape == (10, 5)
@pytest.mark.parametrize("op", [np.fft.fftn, np.fft.ifftn,
np.fft.rfftn, np.fft.irfftn])
def test_s_axes_none(self, op):
x = np.arange(100).reshape(10, 10)
with pytest.warns(match='`axes` should not be `None` if `s`'):
op(x, s=(-1, 5))
@pytest.mark.parametrize("op", [np.fft.fft2, np.fft.ifft2])
def test_s_axes_none_2D(self, op):
x = np.arange(100).reshape(10, 10)
with pytest.warns(match='`axes` should not be `None` if `s`'):
op(x, s=(-1, 5), axes=None)
@pytest.mark.parametrize("op", [np.fft.fftn, np.fft.ifftn,
np.fft.rfftn, np.fft.irfftn,
np.fft.fft2, np.fft.ifft2])
def test_s_contains_none(self, op):
x = random((30, 20, 10))
with pytest.warns(match='array containing `None` values to `s`'):
op(x, s=(10, None, 10), axes=(0, 1, 2))
def test_all_1d_norm_preserving(self):
# verify that round-trip transforms are norm-preserving
x = random(30)
x_norm = np.linalg.norm(x)
n = x.size * 2
func_pairs = [(np.fft.fft, np.fft.ifft),
(np.fft.rfft, np.fft.irfft),
# hfft: order so the first function takes x.size samples
# (necessary for comparison to x_norm above)
(np.fft.ihfft, np.fft.hfft),
]
for forw, back in func_pairs:
for n in [x.size, 2*x.size]:
for norm in [None, 'backward', 'ortho', 'forward']:
tmp = forw(x, n=n, norm=norm)
tmp = back(tmp, n=n, norm=norm)
assert_allclose(x_norm,
np.linalg.norm(tmp), atol=1e-6)
@pytest.mark.parametrize("axes", [(0, 1), (0, 2), None])
@pytest.mark.parametrize("dtype", (complex, float))
@pytest.mark.parametrize("transpose", (True, False))
def test_fftn_out_argument(self, dtype, transpose, axes):
def zeros_like(x):
if transpose:
return np.zeros_like(x.T).T
else:
return np.zeros_like(x)
# tests below only test the out parameter
if dtype is complex:
x = random((10, 5, 6)) + 1j*random((10, 5, 6))
fft, ifft = np.fft.fftn, np.fft.ifftn
else:
x = random((10, 5, 6))
fft, ifft = np.fft.rfftn, np.fft.irfftn
expected = fft(x, axes=axes)
out = zeros_like(expected)
result = fft(x, out=out, axes=axes)
assert result is out
assert_array_equal(result, expected)
expected2 = ifft(expected, axes=axes)
out2 = out if dtype is complex else zeros_like(expected2)
result2 = ifft(out, out=out2, axes=axes)
assert result2 is out2
assert_array_equal(result2, expected2)
@pytest.mark.parametrize("fft", [np.fft.fftn, np.fft.ifftn, np.fft.rfftn])
def test_fftn_out_and_s_interaction(self, fft):
# With s, shape varies, so generally one cannot pass in out.
if fft is np.fft.rfftn:
x = random((10, 5, 6))
else:
x = random((10, 5, 6)) + 1j*random((10, 5, 6))
with pytest.raises(ValueError, match="has wrong shape"):
fft(x, out=np.zeros_like(x), s=(3, 3, 3), axes=(0, 1, 2))
# Except on the first axis done (which is the last of axes).
s = (10, 5, 5)
expected = fft(x, s=s, axes=(0, 1, 2))
out = np.zeros_like(expected)
result = fft(x, s=s, axes=(0, 1, 2), out=out)
assert result is out
assert_array_equal(result, expected)
@pytest.mark.parametrize("s", [(9, 5, 5), (3, 3, 3)])
def test_irfftn_out_and_s_interaction(self, s):
# Since for irfftn, the output is real and thus cannot be used for
# intermediate steps, it should always work.
x = random((9, 5, 6, 2)) + 1j*random((9, 5, 6, 2))
expected = np.fft.irfftn(x, s=s, axes=(0, 1, 2))
out = np.zeros_like(expected)
result = np.fft.irfftn(x, s=s, axes=(0, 1, 2), out=out)
assert result is out
assert_array_equal(result, expected)
@pytest.mark.parametrize(
"dtype",
[np.float32, np.float64, np.complex64, np.complex128])
@pytest.mark.parametrize("order", ["F", 'non-contiguous'])
@pytest.mark.parametrize(
"fft",
[np.fft.fft, np.fft.fft2, np.fft.fftn,
np.fft.ifft, np.fft.ifft2, np.fft.ifftn])
def test_fft_with_order(dtype, order, fft):
# Check that FFT/IFFT produces identical results for C, Fortran and
# non contiguous arrays
rng = np.random.RandomState(42)
X = rng.rand(8, 7, 13).astype(dtype, copy=False)
# See discussion in pull/14178
_tol = 8.0 * np.sqrt(np.log2(X.size)) * np.finfo(X.dtype).eps
if order == 'F':
Y = np.asfortranarray(X)
else:
# Make a non contiguous array
Y = X[::-1]
X = np.ascontiguousarray(X[::-1])
if fft.__name__.endswith('fft'):
for axis in range(3):
X_res = fft(X, axis=axis)
Y_res = fft(Y, axis=axis)
assert_allclose(X_res, Y_res, atol=_tol, rtol=_tol)
elif fft.__name__.endswith(('fft2', 'fftn')):
axes = [(0, 1), (1, 2), (0, 2)]
if fft.__name__.endswith('fftn'):
axes.extend([(0,), (1,), (2,), None])
for ax in axes:
X_res = fft(X, axes=ax)
Y_res = fft(Y, axes=ax)
assert_allclose(X_res, Y_res, atol=_tol, rtol=_tol)
else:
raise ValueError()
@pytest.mark.parametrize("order", ["F", "C"])
@pytest.mark.parametrize("n", [None, 7, 12])
def test_fft_output_order(order, n):
rng = np.random.RandomState(42)
x = rng.rand(10)
x = np.asarray(x, dtype=np.complex64, order=order)
res = np.fft.fft(x, n=n)
assert res.flags.c_contiguous == x.flags.c_contiguous
assert res.flags.f_contiguous == x.flags.f_contiguous
@pytest.mark.skipif(IS_WASM, reason="Cannot start thread")
class TestFFTThreadSafe:
threads = 16
input_shape = (800, 200)
def _test_mtsame(self, func, *args):
def worker(args, q):
q.put(func(*args))
q = queue.Queue()
expected = func(*args)
# Spin off a bunch of threads to call the same function simultaneously
t = [threading.Thread(target=worker, args=(args, q))
for i in range(self.threads)]
[x.start() for x in t]
[x.join() for x in t]
# Make sure all threads returned the correct value
for i in range(self.threads):
assert_array_equal(q.get(timeout=5), expected,
'Function returned wrong value in multithreaded context')
def test_fft(self):
a = np.ones(self.input_shape) * 1+0j
self._test_mtsame(np.fft.fft, a)
def test_ifft(self):
a = np.ones(self.input_shape) * 1+0j
self._test_mtsame(np.fft.ifft, a)
def test_rfft(self):
a = np.ones(self.input_shape)
self._test_mtsame(np.fft.rfft, a)
def test_irfft(self):
a = np.ones(self.input_shape) * 1+0j
self._test_mtsame(np.fft.irfft, a)
def test_irfft_with_n_1_regression():
# Regression test for gh-25661
x = np.arange(10)
np.fft.irfft(x, n=1)
np.fft.hfft(x, n=1)
np.fft.irfft(np.array([0], complex), n=10)
def test_irfft_with_n_large_regression():
# Regression test for gh-25679
x = np.arange(5) * (1 + 1j)
result = np.fft.hfft(x, n=10)
expected = np.array([20., 9.91628173, -11.8819096, 7.1048486,
-6.62459848, 4., -3.37540152, -0.16057669,
1.8819096, -20.86055364])
assert_allclose(result, expected)
@pytest.mark.parametrize("fft", [
np.fft.fft, np.fft.ifft, np.fft.rfft, np.fft.irfft
])
@pytest.mark.parametrize("data", [
np.array([False, True, False]),
np.arange(10, dtype=np.uint8),
np.arange(5, dtype=np.int16),
])
def test_fft_with_integer_or_bool_input(data, fft):
# Regression test for gh-25819
result = fft(data)
float_data = data.astype(np.result_type(data, 1.))
expected = fft(float_data)
assert_array_equal(result, expected)