I am using FFTW and CUFFT in a simulation to deformed a 3D microstructure by applying a load in one direction. I set the boundary conditions for tension in the Y direction, but when I visualize it in Paraview, it appears deformed in the X direction.
I was told that the indexing for FFTs are switched for some axes in FFTW and CUFFT. Why is this? Does this mean I should change my loading direction?