It's probably a problem with your design. Can you send me the Xtmp.mat file? doug
Sid Kundu wrote:
Hi Doug,
I created a new first level analysis along with new contrasts and event numbers for a group of subjects I had previously done analyses on. All but one of the subjects finished selxavg3 without error, but one subject gave the following error:
Saving X matrix to /home/sidkundu/freesurfer/sessions/Heading-TTP/LMV2010_N19_Heading-TTP/bold/TTP-analysis-3/Xtmp.mat Error using svd Input to SVD must not contain NaN or Inf.
Error in cond (line 39) s = svd(A);
Error in fast_selxavg3 (line 248) XCond = cond(XtX);
ERROR: fast_selxavg3() failed\n
I looked at the generated Xtmp.mat file and it shows the design matrix X has all zeros in 2 columns, resulting in NaNs in the same columns for Xn, and corresponding NaNs in XtX. I'm wondering what would cause this or why it would only occur for only one subject.
Sid Kundu Biomedical Engineering Boston University