Unexpected result calculating the determinant of a singular matrix (42S)

[John Keith]

The HP 50 in approximate mode and with flag -54 (the "cheat" flag) set*, returns 0 for both Dave's and Thomas's matrices. I'm surprised that the 42s gives an inexact result, I assumed the internal code for matrix math was essentially the same as the 48/49 series.


* Note that setting the flag removes the "cheat". Also, according to the HP 50 AUR, the basis for setting tiny elements to 0 is that intermediate results are less than 1E-14. It does not say anything about integer values.