Hi,

I had a problem with a higher level analysis:

An exception has been thrown
Runtime error:- detected by Newmat: matrix is singular

Searching the mailing list gave me a possible solution, that this could happen, if the mask includes voxels in the filtered_func_data 4D file with all zeros. In a post about a year ago it was stated that this problem is solved with a new FSL version. However, recently there was a comparable discussion with the result that the mask should not include voxels with all zero. So, is it still a problem when the mask includes zero-voxels? If so, what is the best trick to avoid the creation of a mask as preparatory step in the higher level analysis and instead use an alternative a mask similar as one can do in the first level analysis at the end of the .fsf-file? So far I copied a custom made mask into the gfeat-directory at the beginning of the analysis and made sure that it is write protected. Did work fine until today...

Thanks for the help,
wolf