Dear ptalylor,
Thank you for your immediate reply.It helps me a lot with this problem, I just express your explanation again in my words for confirmation: the "x,y,z extent" information in the header is just preference of showing 3D volume in afni, so it won't change with 3dresample. if i want to change the orientation of the dataset, 3dresample -orient should be used. Is that right?
Typically, the dataset is in the wrong orientation when we want to change the orientation, but how do we confirm it's the wrong orientation? I usually click on one point in the right, anterior, inferior orientation to check if the coordinates are all minus values, is this the right way?
Besides, I found 3drefit can also change the orientation, but only change the sign of the origin, while 3dresample changes both their signs and values.what's running inside, could you help me?
Best Wishes!
Yours,
Peng Ren