Re: [boost] [rfc] A light weight statically typed matrix template class (again?)

From: Steve M. Robbins (steve_at_[hidden])
Date: 2007-12-19 09:57:18

On Tue, Dec 18, 2007 at 03:02:12PM -0700, Dave Steffen wrote:
> On Tuesday 18 December 2007, Martin Bonner wrote:
> > From: Andreas Harnack
> >
> > > If you think that this doesn't belong to the standard, then
> > > please allow me to ask one question: Why is there a complex
> > > number class in the standard and what does it actually do?
> >
> > There is rather less discussion about possible interfaces for complex
> > numbers than for matrices.  (The last time I used matrices in my code, I
> > wanted A=B*C to mean A[i,j] = B[i,j]*C[i,j].)
> 
>   Interesting: that's a direct product, which we hardly ever use.

I don't think that's a direct product; c.f.
http://mathworld.wolfram.com/MatrixDirectProduct.html

Wikipedia suggests it's called the Hadamard (or Schur or entrywise)
product; c.f. http://en.wikipedia.org/wiki/Matrix_multiplication

Yours pedantically,
-Steve