Hmm, I think I agree. Why does leading_coefficient() behave backwards anyway?
On Saturday, 1 December 2012 04:44:10 UTC-8, John Cremona wrote: > > I don't think "monicize" is a word. For polynomials, the function in > Sage is called .monic(): > > sage: x=polygen(QQ) > sage: p=3*x+1 > sage: p.monic() > x + 1/3 > > but I have also never heard of the use of monic for vectors. In any > case, there are (at least) two possible normalizations, depending on > whether you divide by the first or the last nonzero entry. The > convention in Sage for homogeneous coordinates is the latter: > > sage: P2=ProjectiveSpace(QQ,2) > sage: P2([3,4,5]) > (3/5 : 4/5 : 1) > > so there's nothing "normal" in Sage about dividing by the first > nonzero coordinate. > > This suggests the possibility of having both .divide_by_leading() and > .divide_by_trailing(). Here one should note the existing functions > for vectors which are perhaps counter-intuitive: > > sage: v=vector((3,4,5)) > sage: v.leading_coefficient() > 5 > sage: v.trailing_coefficient() > 3 > > All of this makes me thing that (especially in view of the ease of > manually using the preceding two existing functions) it is not worth > adding any new ones. > > John > > On 1 December 2012 02:33, Keshav Kini <kesha...@gmail.com <javascript:>> > wrote: > > Kannappan Sampath <kntr...@gmail.com <javascript:>> writes: > >> Perhaps, I should explain my rationale for the terms I chose, my > >> first preference is `echelonize(v)` (although I wrote it second) > >> because, what the function returns amounts to its reduced row echelon > >> form, if you think of it as 1 x n matrix. > > > > My rationale for "monicize" is the standard term from algebra, "monic > > polynomial" [1], but maybe it's not so relevant here... > > > > [1] http://en.wikipedia.org/wiki/Monic_polynomial > > > > -Keshav > > > > -- > > You received this message because you are subscribed to the Google > Groups "sage-devel" group. > > To post to this group, send email to > > sage-...@googlegroups.com<javascript:>. > > > To unsubscribe from this group, send email to > sage-devel+...@googlegroups.com <javascript:>. > > Visit this group at http://groups.google.com/group/sage-devel?hl=en. > > > > > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To post to this group, send email to sage-devel@googlegroups.com. To unsubscribe from this group, send email to sage-devel+unsubscr...@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel?hl=en.
