Discrete Fourier transforms (scipy.fft) — SciPy v1.15.3 Manual (original) (raw)
Fast Fourier Transforms (FFTs)#
| fft(x[, n, axis, norm, overwrite_x, ...]) | Compute the 1-D discrete Fourier Transform. |
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| ifft(x[, n, axis, norm, overwrite_x, ...]) | Compute the 1-D inverse discrete Fourier Transform. |
| fft2(x[, s, axes, norm, overwrite_x, ...]) | Compute the 2-D discrete Fourier Transform |
| ifft2(x[, s, axes, norm, overwrite_x, ...]) | Compute the 2-D inverse discrete Fourier Transform. |
| fftn(x[, s, axes, norm, overwrite_x, ...]) | Compute the N-D discrete Fourier Transform. |
| ifftn(x[, s, axes, norm, overwrite_x, ...]) | Compute the N-D inverse discrete Fourier Transform. |
| rfft(x[, n, axis, norm, overwrite_x, ...]) | Compute the 1-D discrete Fourier Transform for real input. |
| irfft(x[, n, axis, norm, overwrite_x, ...]) | Computes the inverse of rfft. |
| rfft2(x[, s, axes, norm, overwrite_x, ...]) | Compute the 2-D FFT of a real array. |
| irfft2(x[, s, axes, norm, overwrite_x, ...]) | Computes the inverse of rfft2 |
| rfftn(x[, s, axes, norm, overwrite_x, ...]) | Compute the N-D discrete Fourier Transform for real input. |
| irfftn(x[, s, axes, norm, overwrite_x, ...]) | Computes the inverse of rfftn |
| hfft(x[, n, axis, norm, overwrite_x, ...]) | Compute the FFT of a signal that has Hermitian symmetry, i.e., a real spectrum. |
| ihfft(x[, n, axis, norm, overwrite_x, ...]) | Compute the inverse FFT of a signal that has Hermitian symmetry. |
| hfft2(x[, s, axes, norm, overwrite_x, ...]) | Compute the 2-D FFT of a Hermitian complex array. |
| ihfft2(x[, s, axes, norm, overwrite_x, ...]) | Compute the 2-D inverse FFT of a real spectrum. |
| hfftn(x[, s, axes, norm, overwrite_x, ...]) | Compute the N-D FFT of Hermitian symmetric complex input, i.e., a signal with a real spectrum. |
| ihfftn(x[, s, axes, norm, overwrite_x, ...]) | Compute the N-D inverse discrete Fourier Transform for a real spectrum. |
Discrete Sin and Cosine Transforms (DST and DCT)#
| dct(x[, type, n, axis, norm, overwrite_x, ...]) | Return the Discrete Cosine Transform of arbitrary type sequence x. |
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| idct(x[, type, n, axis, norm, overwrite_x, ...]) | Return the Inverse Discrete Cosine Transform of an arbitrary type sequence. |
| dctn(x[, type, s, axes, norm, overwrite_x, ...]) | Return multidimensional Discrete Cosine Transform along the specified axes. |
| idctn(x[, type, s, axes, norm, overwrite_x, ...]) | Return multidimensional Inverse Discrete Cosine Transform along the specified axes. |
| dst(x[, type, n, axis, norm, overwrite_x, ...]) | Return the Discrete Sine Transform of arbitrary type sequence x. |
| idst(x[, type, n, axis, norm, overwrite_x, ...]) | Return the Inverse Discrete Sine Transform of an arbitrary type sequence. |
| dstn(x[, type, s, axes, norm, overwrite_x, ...]) | Return multidimensional Discrete Sine Transform along the specified axes. |
| idstn(x[, type, s, axes, norm, overwrite_x, ...]) | Return multidimensional Inverse Discrete Sine Transform along the specified axes. |
Fast Hankel Transforms#
| fht(a, dln, mu[, offset, bias]) | Compute the fast Hankel transform. |
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| ifht(A, dln, mu[, offset, bias]) | Compute the inverse fast Hankel transform. |
Helper functions#
| fftshift(x[, axes]) | Shift the zero-frequency component to the center of the spectrum. |
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| ifftshift(x[, axes]) | The inverse of fftshift. |
| fftfreq(n[, d, xp, device]) | Return the Discrete Fourier Transform sample frequencies. |
| rfftfreq(n[, d, xp, device]) | Return the Discrete Fourier Transform sample frequencies (for usage with rfft, irfft). |
| fhtoffset(dln, mu[, initial, bias]) | Return optimal offset for a fast Hankel transform. |
| next_fast_len(target[, real]) | Find the next fast size of input data to fft, for zero-padding, etc. |
| prev_fast_len(target[, real]) | Find the previous fast size of input data to fft. |
| set_workers(workers) | Context manager for the default number of workers used in scipy.fft |
| get_workers() | Returns the default number of workers within the current context |
Backend control#
| set_backend(backend[, coerce, only]) | Context manager to set the backend within a fixed scope. |
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| skip_backend(backend) | Context manager to skip a backend within a fixed scope. |
| set_global_backend(backend[, coerce, only, ...]) | Sets the global fft backend |
| register_backend(backend) | Register a backend for permanent use. |