I want to calculate the variation of dataset. I have used 3dTstat -stdev, but the result doesn’t seem well. So I want to try the latter volume minus the volume, for example,sub-brick#2-#1，#3-#2，#4-#3…In this case,what program should I use? If no program can do this , can I use 3dTcat to select every 2 sub-brick by using the selection list,like red+orig[0…$(2)] and blue+orig[1…$(2)],then blue-red using 3dcalc?
Thanks a lot