jax.numpy.fft.ifftshift — JAX documentation (original) (raw)

jax.numpy.fft.ifftshift#

jax.numpy.fft.ifftshift(x, axes=None)[source]#

The inverse of jax.numpy.fft.fftshift().

JAX implementation of numpy.fft.ifftshift().

Parameters:

• x (ArrayLike) – N-dimensional array array of frequencies.
• axes (None | int | Sequence _[_int]) – optional integer or sequence of integers specifying which axes to shift. If None (default), then shift all axes.

Returns:

A shifted copy of x.

Return type:

Array

See also

• jax.numpy.fft.fftshift(): inverse of ifftshift.
• jax.numpy.fft.fftfreq(): generate FFT frequencies.

Examples

Generate FFT frequencies with fftfreq():

freq = jnp.fft.fftfreq(5) freq Array([ 0. , 0.2, 0.4, -0.4, -0.2], dtype=float32)

Use fftshift() to shift the zero-frequency entry to the middle of the array:

shifted_freq = jnp.fft.fftshift(freq) shifted_freq Array([-0.4, -0.2, 0. , 0.2, 0.4], dtype=float32)

Unshift with ifftshift to recover the original frequencies:

jnp.fft.ifftshift(shifted_freq) Array([ 0. , 0.2, 0.4, -0.4, -0.2], dtype=float32)