### Question:
SpectralUtils { public static void fft2D_inplace(ComplexDoubleMatrix A) { ComplexDoubleMatrix aTemp = A.transpose(); DoubleFFT_2D fft2d = new DoubleFFT_2D(aTemp.rows, aTemp.columns); fft2d.complexForward(aTemp.data); A.data = aTemp.transpose().data; }  static void fft1D_inplace(ComplexDoubleMatrix vector, final int fftLength); static void invfft1D_inplace(ComplexDoubleMatrix vector, final int fftLength); static ComplexDoubleMatrix fft1D(ComplexDoubleMatrix vector, final int fftLength); static ComplexDoubleMatrix invfft1D(ComplexDoubleMatrix vector, final int fftLength); static ComplexDoubleMatrix fft(ComplexDoubleMatrix inMatrix, final int dimension); static ComplexDoubleMatrix invfft(ComplexDoubleMatrix inMatrix, final int dimension); static void fft_inplace(ComplexDoubleMatrix inMatrix, int dimension); static void invfft_inplace(ComplexDoubleMatrix inMatrix, int dimension); static void fft2D_inplace(ComplexDoubleMatrix A); static ComplexDoubleMatrix fft2D(ComplexDoubleMatrix inMatrix); static void fft2D_inplace(DoubleMatrix A); static void invfft2D_inplace(ComplexDoubleMatrix A); static ComplexDoubleMatrix invfft2d(ComplexDoubleMatrix inMatrix); static ComplexDoubleMatrix fftshift(ComplexDoubleMatrix inMatrix); static DoubleMatrix fftshift(DoubleMatrix inMatrix); static void fftshift_inplace(ComplexDoubleMatrix inMatrix); static void fftshift_inplace(DoubleMatrix inMatrix); static ComplexDoubleMatrix ifftshift(ComplexDoubleMatrix inMatrix); static DoubleMatrix ifftshift(DoubleMatrix inMatrix); static void ifftshift_inplace(ComplexDoubleMatrix inMatrix); static void ifftshift_inplace(DoubleMatrix inMatrix);  }### Answer:
@Test public void testFft2D_inplace() throws Exception { ComplexDoubleMatrix fftMatrix_2D_ACTUAL = complexMatrix_EXPECTED.dup(); SpectralUtils.fft2D_inplace(fftMatrix_2D_ACTUAL); Assert.assertEquals(fftMatrix_2D_EXPECTED, fftMatrix_2D_ACTUAL); ComplexDoubleMatrix fftMatrix_2D_ACTUAL_2 = complexMatrix_EXPECTED_2.dup(); SpectralUtils.fft2D_inplace(fftMatrix_2D_ACTUAL_2); Assert.assertEquals(fftMatrix_2D_EXPECTED_2, fftMatrix_2D_ACTUAL_2); }