I have an issue with processing my data (acquired at Siemens Prisma 3T) by
gradunwarp v1.0.2, downloaded from
It crashed with my coef.grad file by producing "array index out of bounds"
error in coef_file_parse routine.
I managed to get it working by increasing siemens_cas=20 in core/globals.py
The corrected images look reasonable, with deformation going to maximum approx
1-2 mm in off-isocenter regions.
Since I am not familiar with internals of gradunwarp, I would like to assure
myself the routine with my modification works OK and there is no other unwanted
consequence by increasing siemens_cas. Could you please comment on?
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