afni.nimh.nih.gov

Hi Krista,

Does your file have negative values in it, or something strange
like that? That might have happened if it should have been
byte-swapped at creation time. Since you say that using the
expression step(b+1469) has strange results (which should
not be the case), I'm curious about what sort of numbers are
in the dataset.

What is the output of "3dinfo detrend+orig | head -20"?
How about the same command using mean+orig?

- rick