In my mind the inverse of a non invertible matrix is a domain error. But I have become aware of otherwise
JVERSION Engine: j902/j64avx2/windows Release-a: commercial/2020-12-05T13:36:01 Library: 9.02.08 Qt IDE: 1.9.2s/5.12.10(5.12.10) Platform: Win 64 Installer: J902 install InstallPath: c:/program files/j902 Contact: www.jsoftware.com (Also 9.03 MacOs) Likely due to avx changes in 9.01 %. i. 4 4 |domain error | %.i.4 4 %. 3 3$1 |NaN error %. i. 3 3 _. _. _. _. _. _. _. _. _. Run (;%.)a=:(,+/)?2 3$4 a few times and see all three types of results. I find the array of indeterminants disquieting but I am not sure it is worth doing anything about. Thoughts? Back to grading... Best, Cliff ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
