fftshift {AIUQ} | R Documentation |
fftshift
Description
Rearranges a 2D Fourier transform x by shifting the zero-frequency component to the center of the matrix.
Usage
fftshift(x, dim = -1)
Arguments
x |
square matrix input with odd number of rows and columns |
dim |
shift method. See 'Details'. |
Details
By default, dim=-1
, swaps the first quadrant of x with the
third, and the second quadrant with the fourth. If dim=1
, swaps rows 1
to middle with rows (middle+1) to end. If dim=2
, swaps columns 1
to middle with columns (middle+1) to end. If dim=3
, reverse fftshift.
Value
Shifted matrix.
Author(s)
Yue He [aut], Xubo Liu [aut], Mengyang Gu [aut, cre]
Examples
library(AIUQ)
(m <- matrix(0:8,3,3))
fftshift(m)
[Package AIUQ version 0.5.2 Index]