> >>> This might also help resolve the back-burner project of mine to make > >>> echelon_form for integer matrices return the typical linear algebra > >>> definition of rref, i.e., the 'frac' method above. Currently, the > >>> decision is to make echelon_form behave like 'frac' above, and make > >>> hermite_form behave like 'row_reduction' above. Making echelon_form > >>> support the arguments above seems like it would be a better > >>> resolution > >>> and provide a clear deprecation path. However, the decision would > >>> imply > >>> that the default be 'frac' instead of 'row_reduction'. On the other > >>> hand, it'd be great if things were consistent across base rings. > >>> What > >>> is the possibility of making the default to be 'frac' over polynomial > >>> rings? (Sorry if this question is laughable or repulsive...) > > >> +1 to making the default be over the fraction field in all cases, and > >> having a different > >> command or non-default option for the non-fraction field version. > >> Having just taught > >> echelon forms to undergrads I now very much see Jason's point. > > > +1 from me too. However, IIRC it used to be this way and then got > > changed. Does anyone remember the rational for why?
The fact that this doesn't work (hence requiring that one define matrices over QQ, which is quite confusing for students who haven't - and, for non-majors, won't - take algebra) is the main reason our linear algebra person does not use Sage in the course. He would love to, though, because Octave does everything with floats or whatever which is not always appropriate. For what it's worth, - kcrisman --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
