Defined in tensorflow/python/ops/

See the guide: Spectral Functions > Discrete Fourier Transforms

3D real-valued fast Fourier transform.

Computes the 3-dimensional discrete Fourier transform of a real-valued signal over the inner-most 3 dimensions of input.

Since the DFT of a real signal is Hermitian-symmetric, RFFT3D only returns the fft_length / 2 + 1 unique components of the FFT for the inner-most dimension of output: the zero-frequency term, followed by the fft_length / 2 positive-frequency terms.

Along each axis RFFT3D is computed on, if fft_length is smaller than the corresponding dimension of input, the dimension is cropped. If it is larger, the dimension is padded with zeros.


  • input: A Tensor of type float32. A float32 tensor.
  • fft_length: A Tensor of type int32. An int32 tensor of shape [3]. The FFT length for each dimension.
  • name: A name for the operation (optional).


A Tensor of type complex64.