IFFTSHIFT Inverse Shift FFT Output
ifftshiftfunction shifts the DC component (zero-frequency) of the output from the center of the array back to the first position and iseffectively the inverse of
fftshift. For vectors this means swapping the two halves of the vector. For matrices, the first and third quadrants are swapped. So on for N-dimensional arrays. The syntax for its use is
y = ifftshift(x).
Alternately, you can specify that only one dimension be shifted
y = ifftshift(x,dim).