jax.numpy.fft.ihfft#

jax.numpy.fft.ihfft(a,n=None,axis=-1,norm=None)[source]#

Compute a 1-D inverse FFT of an array whose spectrum has Hermitian-symmetry.

JAX implementation ofnumpy.fft.ihfft().

Parameters:

• a (ArrayLike) – input array.

• n (int |None) – optional, int. Specifies the effective dimension of the input alongaxis.If not specified, it will default to the dimension of input alongaxis.

• axis (int) – optional, int, default=-1. Specifies the axis along which the transformis computed. If not specified, the transform is computed along axis -1.

• norm (str |None) – optional, string. The normalization mode. “backward”, “ortho” and “forward”are supported. Default is “backward”.

Returns:

An array containing one-dimensional discrete Fourier transform ofa byexploiting its inherent Hermitian symmetry. The dimension of the array alongaxis is(n/2)+1, ifn is even and(n+1)/2, ifn is odd.

Return type:

Array

See also

• jax.numpy.fft.hfft(): Computes a one-dimensional FFT of an arraywhose spectrum has Hermitian symmetry.

• jax.numpy.fft.fft(): Computes a one-dimensional discrete Fouriertransform.

• jax.numpy.fft.rfft(): Computes a one-dimensional discrete Fouriertransform of a real-valued input.

Examples

>>>x=jnp.array([[1,3,5,7],...[2,4,6,8]])>>>jnp.fft.ihfft(x)Array([[ 4.+0.j, -1.-1.j, -1.-0.j],       [ 5.+0.j, -1.-1.j, -1.-0.j]], dtype=complex64)

Whenn=4 andaxis=0, dimension of the transform alongaxis0 willbe(4/2)+1=3 and dimension along other axes will be same as that of input.

>>>jnp.fft.ihfft(x,n=4,axis=0)Array([[ 0.75+0.j ,  1.75+0.j ,  2.75+0.j ,  3.75+0.j ],       [ 0.25+0.5j,  0.75+1.j ,  1.25+1.5j,  1.75+2.j ],       [-0.25-0.j , -0.25-0.j , -0.25-0.j , -0.25-0.j ]], dtype=complex64)