transformed coordinates of 2-d fft

i have a function varying in space and time. i have done fft of the function and got the data. now i want to plot it against the transformed co-ordinates. but i am not able to find the transformed co-ordinates. x=[-10:.01:10]; t=[-5:.005:5]; a=sin(x); b=sin(2*x); c=sin(5*t); d=sin(12*t); e=cos(x); f=cos(2*x); g=cos(5*t); h=cos(12*t); k=fft(a); l=fft(b); m=fft(c); n=fft(d); p=fft(e); q=fft(f); r=fft(g); s=fft(h); t=20*((k'*r)-(p'*m))+11*((q'*s)-(l'*n)); t1=fftshift(t); t2=abs(t1); ow how to plot t2 gainst the ransformed co-ordinates.??? help please