def test_fscale(self):
# test for an even number of samples
res = [0, 100, 200, 300, 400, 500, -400, -300, -200, -100],
self.assertTrue(np.all(np.abs(ft.fscale(10, 0.001) - res) < 1e-6))
# test for an odd number of samples
res = [0, 90.9090909090909, 181.818181818182, 272.727272727273, 363.636363636364,
454.545454545455, -454.545454545455, -363.636363636364, -272.727272727273,
-181.818181818182, -90.9090909090909],
self.assertTrue(np.all(np.abs(ft.fscale(11, 0.001) - res) < 1e-6))
def test_fexpand(self):
# test odd input
res = np.random.rand(11)
X = ft.freduce(np.fft.fft(res))
R = np.real(np.fft.ifft(ft.fexpand(X, 11)))
self.assertTrue(np.all((res - R) < 1e-6))
# test even input
res = np.random.rand(12)
X = ft.freduce(np.fft.fft(res))
R = np.real(np.fft.ifft(ft.fexpand(X, 12)))
self.assertTrue(np.all((res - R) < 1e-6))
# test with a 2 dimensional input along last dimension
res = np.random.rand(2, 12)
X = ft.freduce(np.fft.fft(res))
R = np.real(np.fft.ifft(ft.fexpand(X, 12)))
self.assertTrue(np.all((res - R) < 1e-6))
# test with a 3 dimensional input along last dimension
res = np.random.rand(3, 5, 12)
X = ft.freduce(np.fft.fft(res))
R = np.real(np.fft.ifft(ft.fexpand(X, 12)))
self.assertTrue(np.all((res - R) < 1e-6))
# test with 2 dimensional input along first dimension
fs = np.transpose(
mat.repmat(ft.fscale(500, 0.001, one_sided=True), 4, 1))
self.assertTrue(ft.fexpand(fs, 500, axis=0).shape == (500, 4))
def test_freduce(self):
# test with 1D arrays
fs = np.fft.fftfreq(5)
self.assertTrue(np.all(ft.freduce(fs) == fs[:-2]))
fs = np.fft.fftfreq(6)
self.assertTrue(np.all(ft.freduce(fs) == fs[:-2]))
# test 2D arrays along both dimensions
fs = mat.repmat(ft.fscale(500, 0.001), 4, 1)
self.assertTrue(ft.freduce(fs).shape == (4, 251))
self.assertTrue(ft.freduce(np.transpose(fs), axis=0).shape == (251, 4))
