# tensorplay.fft._transforms API

Source: https://www.tensorplay.cn/docs/api/tensorplay.fft._transforms.html

## Functions 18

[#](#api-tensorplay.fft._transforms.fft)

### fft

function[Full reference ↗](/docs/generated/tensorplay.fft._transforms.fft.html)

```python
tensorplay.fft._transforms.fft(input, n=None, dim=-1, norm=None, *, out=None)
```

Computes the one-dimensional discrete Fourier transform.

Parameters:

- input ([Tensor](/docs/generated/tensorplay.Tensor.html#tensorplay.Tensor)) – the input tensor

- n ([int](https://docs.python.org/3/builtins/functions.html#int), optional) – signal length; zero-pads/truncates dim

- dim ([int](https://docs.python.org/3/builtins/functions.html#int), optional) – the dimension to transform. Default: -1

- norm ([str](https://docs.python.org/3/builtins/stdtypes.html#str), optional) – "backward", "forward" or "ortho". Default: None (= "backward")

[#](#api-tensorplay.fft._transforms.fft2)

### fft2

function[Full reference ↗](/docs/generated/tensorplay.fft._transforms.fft2.html)

```python
tensorplay.fft._transforms.fft2(input, s=None, dim=(-2, -1), norm=None, *, out=None)
```

Computes the two-dimensional discrete Fourier transform.

[#](#api-tensorplay.fft._transforms.fftn)

### fftn

function[Full reference ↗](/docs/generated/tensorplay.fft._transforms.fftn.html)

```python
tensorplay.fft._transforms.fftn(input, s=None, dim=None, norm=None, *, out=None)
```

Computes the N-dimensional discrete Fourier transform over dim.

dim defaults to the last len(s) dimensions when s is
given and to every dimension otherwise; an entry of -1 in s
keeps that dimension’s length.

[#](#api-tensorplay.fft._transforms.hfft)

### hfft

function[Full reference ↗](/docs/generated/tensorplay.fft._transforms.hfft.html)

```python
tensorplay.fft._transforms.hfft(input, n=None, dim=-1, norm=None, *, out=None)
```

Computes the 1-D FFT of a Hermitian-symmetric spectrum; real output.

Equivalent to [irfft()](/docs/generated/tensorplay.fft._transforms.irfft.html#tensorplay.fft._transforms.irfft) applied to input.conj(); n is the
output length (default 2 * (input.size(dim) - 1)).

[#](#api-tensorplay.fft._transforms.hfft2)

### hfft2

function[Full reference ↗](/docs/generated/tensorplay.fft._transforms.hfft2.html)

```python
tensorplay.fft._transforms.hfft2(input, s=None, dim=(-2, -1), norm=None, *, out=None)
```

Two-dimensional FFT of a Hermitian-symmetric spectrum; real output.

[#](#api-tensorplay.fft._transforms.hfftn)

### hfftn

function[Full reference ↗](/docs/generated/tensorplay.fft._transforms.hfftn.html)

```python
tensorplay.fft._transforms.hfftn(input, s=None, dim=None, norm=None, *, out=None)
```

N-dimensional FFT of a Hermitian-symmetric spectrum; real output.

The forward transform over the leading transformed dimensions, then
[hfft()](/docs/generated/tensorplay.fft._transforms.hfft.html#tensorplay.fft._transforms.hfft) (conjugate + complex-to-real) along the final one.

[#](#api-tensorplay.fft._transforms.ifft)

### ifft

function[Full reference ↗](/docs/generated/tensorplay.fft._transforms.ifft.html)

```python
tensorplay.fft._transforms.ifft(input, n=None, dim=-1, norm=None, *, out=None)
```

Computes the one-dimensional inverse discrete Fourier transform.

[#](#api-tensorplay.fft._transforms.ifft2)

### ifft2

function[Full reference ↗](/docs/generated/tensorplay.fft._transforms.ifft2.html)

```python
tensorplay.fft._transforms.ifft2(input, s=None, dim=(-2, -1), norm=None, *, out=None)
```

Computes the two-dimensional inverse discrete Fourier transform.

[#](#api-tensorplay.fft._transforms.ifftn)

### ifftn

function[Full reference ↗](/docs/generated/tensorplay.fft._transforms.ifftn.html)

```python
tensorplay.fft._transforms.ifftn(input, s=None, dim=None, norm=None, *, out=None)
```

Computes the N-dimensional inverse discrete Fourier transform.

[#](#api-tensorplay.fft._transforms.ihfft)

### ihfft

function[Full reference ↗](/docs/generated/tensorplay.fft._transforms.ihfft.html)

```python
tensorplay.fft._transforms.ihfft(input, n=None, dim=-1, norm=None, *, out=None)
```

Computes the inverse of [hfft()](/docs/generated/tensorplay.fft._transforms.hfft.html#tensorplay.fft._transforms.hfft); one-sided complex output.

Equivalent to the conjugate of [rfft()](/docs/generated/tensorplay.fft._transforms.rfft.html#tensorplay.fft._transforms.rfft) of the real input, scaled
as an inverse transform; n zero-pads/truncates the input along
dim.

[#](#api-tensorplay.fft._transforms.ihfft2)

### ihfft2

function[Full reference ↗](/docs/generated/tensorplay.fft._transforms.ihfft2.html)

```python
tensorplay.fft._transforms.ihfft2(input, s=None, dim=(-2, -1), norm=None, *, out=None)
```

Two-dimensional counterpart of [ihfft()](/docs/generated/tensorplay.fft._transforms.ihfft.html#tensorplay.fft._transforms.ihfft).

[#](#api-tensorplay.fft._transforms.ihfftn)

### ihfftn

function[Full reference ↗](/docs/generated/tensorplay.fft._transforms.ihfftn.html)

```python
tensorplay.fft._transforms.ihfftn(input, s=None, dim=None, norm=None, *, out=None)
```

Inverse of [hfftn()](/docs/generated/tensorplay.fft._transforms.hfftn.html#tensorplay.fft._transforms.hfftn): [ihfft()](/docs/generated/tensorplay.fft._transforms.ihfft.html#tensorplay.fft._transforms.ihfft) along the final transformed
dimension, then the inverse transform over the remaining dimensions.

[#](#api-tensorplay.fft._transforms.irfft)

### irfft

function[Full reference ↗](/docs/generated/tensorplay.fft._transforms.irfft.html)

```python
tensorplay.fft._transforms.irfft(input, n=None, dim=-1, norm=None, *, out=None)
```

Computes the inverse of [rfft()](/docs/generated/tensorplay.fft._transforms.rfft.html#tensorplay.fft._transforms.rfft); n is the output length.

[#](#api-tensorplay.fft._transforms.irfft2)

### irfft2

function[Full reference ↗](/docs/generated/tensorplay.fft._transforms.irfft2.html)

```python
tensorplay.fft._transforms.irfft2(input, s=None, dim=(-2, -1), norm=None, *, out=None)
```

Computes the inverse of [rfft2()](/docs/generated/tensorplay.fft._transforms.rfft2.html#tensorplay.fft._transforms.rfft2).

[#](#api-tensorplay.fft._transforms.irfftn)

### irfftn

function[Full reference ↗](/docs/generated/tensorplay.fft._transforms.irfftn.html)

```python
tensorplay.fft._transforms.irfftn(input, s=None, dim=None, norm=None, *, out=None)
```

Inverse of [rfftn()](/docs/generated/tensorplay.fft._transforms.rfftn.html#tensorplay.fft._transforms.rfftn); s[-1] is the real output size
(default 2 * (input.size(dim[-1]) - 1)).

[#](#api-tensorplay.fft._transforms.rfft)

### rfft

function[Full reference ↗](/docs/generated/tensorplay.fft._transforms.rfft.html)

```python
tensorplay.fft._transforms.rfft(input, n=None, dim=-1, norm=None, *, out=None)
```

Computes the one-dimensional FFT of real input, one-sided output.

[#](#api-tensorplay.fft._transforms.rfft2)

### rfft2

function[Full reference ↗](/docs/generated/tensorplay.fft._transforms.rfft2.html)

```python
tensorplay.fft._transforms.rfft2(input, s=None, dim=(-2, -1), norm=None, *, out=None)
```

Computes the two-dimensional FFT of real input.

[#](#api-tensorplay.fft._transforms.rfftn)

### rfftn

function[Full reference ↗](/docs/generated/tensorplay.fft._transforms.rfftn.html)

```python
tensorplay.fft._transforms.rfftn(input, s=None, dim=None, norm=None, *, out=None)
```

N-dimensional FFT of real input; one-sided along the last listed dim.