How to reduce the grid size of 3D matrix, (quarter of its original size)

I have grid data, (X,Y,T) x=lon,y=lat,t=time. The size of the data is (281*321*60), which is 0.25*0.25 grid data. I want to make it 1*1 grid. The final result should be (71*72*60). Kindly help me to do this. I know, how to interpolate and increase the resolution, but no idea how to reduce the resolution and increase the grid size. Thank you.

Answer 1

[Simon Chan]

Suppose A is your data where size is (281*321*60), try the following:

[Ny,Nx,~] = size(A);
idx1 = 1:4:Ny;
idx2 = 1:4:Nx;
B = A(idx1,idx2,:);

Noticed that the size of the result, B is (71*81*60)

size(B)

71 81 60

[Dushantha Sandaruwan WIJENDRA NAIDHELAGE]

Thank you dear Simon, it is perfectly working.