Re: [sage-devel] Adjoint of a matrix

2010-12-02 Thread Gonzalo Tornaria
On Thu, Dec 2, 2010 at 7:16 AM, John Cremona wrote: > What you call the classical adjoint is really the adjugate.  That is > abbreviated to adj, and since there is also an adjoint, it is a common > error to call the adjugate the adjoint. Do you have a reference for this convention? I had never se

Re: [sage-devel] Adjoint of a matrix

2010-12-02 Thread John Cremona
My opinion: What you call the classical adjoint is really the adjugate. That is abbreviated to adj, and since there is also an adjoint, it is a common error to call the adjugate the adjoint. I would not be surprised if there plenty of elementary linear algebra texts out there who describe adj(A)

[sage-devel] Adjoint of a matrix

2010-12-01 Thread Rob Beezer
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." H