On Thu, Jan 26, 2012 at 12:19 PM, Jason Grout <jason-s...@creativetrax.com> wrote: > On 1/26/12 12:13 PM, Robert Bradshaw wrote: >> >> To get a quick sense of what people think about this, I've decided to >> rephrase this as a survey. To be clear, though this coincides with >> Matlab syntax, the intent is not to try to make Sage a Matlab clone, >> rather it is to add a missing feature to Sage. >> >> Should [a, b; c, d] be a valid syntax for matrix construction in Sage? >> >> [ ] Yes, I love this syntax! It would be make life better for me and >> my students. >> [ ] I wouldn't oppose, but may require some convincing. >> [ ] No, that's a horrible idea. > > > > I waffle between Yes, and Yes with convincing. I'm trying it out now to see > how I feel about it. I feel like we shouldn't extend python too much, but > this syntax is very tempting. > > > >> >> Why? >> >> >> Should the default basering be more linear-algebra friendly? E.g. R -> >> Frac(R), RR -> RDF. >> >> [ ] Yes, that would take away a lot of pain/be what I'd have to >> specify manually anyway. >> [ ] Could be handy, but the drawbacks are significant. >> [ ] No, matrices over QQ are for sissies, real mathematicians work >> over ZZ unless otherwise specified. > > > I should just note several areas that ZZ matrices come up short > (intuitively) when you assume you are usually working over fields: > > sage: a=[1,2; 3,4] > sage: a[0,0]=1/2 > (error...) > sage: a.rational_form() > (error...) > sage: a.rescale_row(1/2) > (error...though the error message is a little more helpful and says to use > with_rescaled_row...) > > I agree mostly with the people who say that [] and matrix() should be > consistent. I've resigned myself to always declaring my ring as QQ, etc.
I would be *more* OK with changing the default base ring in matrix to be the fraction field. William > > > Thanks, > > Jason > > -- > To post to this group, send an email to sage-devel@googlegroups.com > To unsubscribe from this group, send an email to > sage-devel+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/sage-devel > URL: http://www.sagemath.org -- William Stein Professor of Mathematics University of Washington http://wstein.org -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
