Emmanuel Thomé wrote: > On 24 juin, 07:50, Jason Grout <[email protected]> wrote: >> And 5. Compare (maybe wrap??) to the nice LU decomposition routine that >> already exists in sympy! I just found this. It looks like very nice >> work. I should probably look at sympy more often when there are missing >> bits in Sage! > > For symbolic matrices, comparisons seem to give a clear advantage to > the sympy code. Think I'll go for that. > > (as for brokenness of your patch for symbolic matrices, the problem > isn't as much inexactness as undecidability of comparisons. Because of > that, partial pivoting sticks with a fake zero pivot, which obviously > fails).
Yes, that's what I found too. My "solution" is to just stick with partial pivoting in the RR/RDF or CC/CDF cases. Note that partial pivoting also fails in the padic case since the abs() function is not defined; hence the other kludge in the code. That's why I decided it wasn't an exact/inexact thing, but rather a RDF/RR/CDF/CC versus anything else thing. Thanks, Jason --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
