Right, "adjoint" should mean "conjugate transpose", and not "classical adjoint/adjugate". But for "conjugate transpose" one can just introduce operator ^*, as usually the conjugate transpose of $A$ is denoted by $A^*$.
Dunno how much Sage code this would break, though... Dmitrii On Dec 2, 12:47 pm, Rob Beezer <goo...@beezer.cotse.net> wrote: > What does the "adjoint of a matrix" mean to you? > > I was brought up to understand it to mean the transpose of the matrix > of signed minors, a matrix close to being the inverse of the > original. Poking around (Wikipedia, Planet Math, Math World) would > imply this is known as the "classical adjoint." Hmmm, I'm not that > old. Anyway, it is also known now as the "adjugate matrix." > > It seems that the term "adjoint" is now more commonly used for the > conjugate-transpose of a matrix (and for vectors) and that's what I > find in most any relatively new textbook on matrix algebra. > > Presently, in Sage, "adjoint" gives the "classical" interpretation. I > would much prefer to define and implement the adjoint of a matrix to > be the conjugate transpose. So two questions: > > 1. Thoughts on what "adjoint" should be? > > 2. If adjoint were to be redefined to a more modern interpretation, > its current use could be aliased to "adjugate" and deprecated, but > that won't make it available for reuse until the deprecation period > runs its course. Any precedent, or techniques, for radically > redefining a method name? > > Rob -- 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
