separation of real and imaginary part in fft2.

if i m finding fft2 for an image, then how do i separate the real and the imaginary part of the output.

is it something like this, the thing is im getting an error at a latter stage and im not quite sure if its because of this real/imaginary separation or use of cart2pol is wrong..?

   P=imread('D:\clone DB\3.jpg');
P=imresize(P,[64 64]);
D=fft2(double(P));
D=uint8(D);
A=fftshift(real(D));
B=fftshift(imag(D));
g = cart2pol(A,B);