# Discrete Fourier Transform

The following tables show discrete fourier transform provided by NLCPy.

## Standard FFTs

 `nlcpy.fft.fft` Computes the one-dimensional discrete fourier transform. `nlcpy.fft.ifft` Computes the one-dimensional inverse discrete fourier transform. `nlcpy.fft.fft2` Computes the 2-dimensional discrete fourier transform. `nlcpy.fft.ifft2` Computes the 2-dimensional inverse discrete fourier transform. `nlcpy.fft.fftn` Computes the n-dimensional discrete fourier transform. `nlcpy.fft.ifftn` Computes the n-dimensional inverse discrete fourier transform.

## Real FFTs

 `nlcpy.fft.rfft` Computes the one-dimensional discrete fourier transform for a real array. `nlcpy.fft.irfft` Computes the inverse of the n-point DFT for a real array. `nlcpy.fft.rfft2` Computes the 2-dimensional FFT of a real array. `nlcpy.fft.irfft2` Computes the 2-dimensional inverse FFT of a real array. `nlcpy.fft.rfftn` Computes the n-dimensional discrete fourier transform for a real array. `nlcpy.fft.irfftn` Computes the inverse of the n-dimensional FFT of a real array.

## Hermitian FFTs

 `nlcpy.fft.hfft` Computes the FFT of a signal that has Hermitian symmetry, i.e., a real spectrum. `nlcpy.fft.ihfft` Computes the inverse FFT of a signal that has Hermitian symmetry.

## Helper routines

 `nlcpy.fft.fftfreq` Returns the Discrete fourier transform sample frequencies. `nlcpy.fft.rfftfreq` Returns the Discrete fourier transform sample frequencies (for usage with `rfft()`, `irfft()`). `nlcpy.fft.fftshift` Shifts the zero-frequency component to the center of the spectrum. `nlcpy.fft.ifftshift` The inverse of fftshift.