Re: [eigen] overriding scalar_X_op for auto-dif?

[Bob Carpenter <carp@xxxxxxxxxxx>]

Thanks so much for getting back to me so quickly
on this.  I tried overloading scalar_product_traits
and NumTraits, but still no luck getting multiplication
of an auto-dif matrix times a double matrix to compile.

I'd MUCH rather just overload the basic ops for now.
Later,  I can optimize with expressions and hand-coded
gradients for some cases without disturbing the API.
I'm afraid your auto-dif scalar code's a bit beyond
my current understanding of Eigen and C++ templates.

I've attached a small tar.gz ball.  Check out the
README.txt, which shows how to run our reverse-mode
auto-dif, has an example using Eigen auto-dif var
multiplication which works fine, and then a demo that
doesn't compile using double * auto-dif variables.
I include the specialization of scalar_product_traits
you suggested (with both orders), as well as NumTraits,
but still no luck.

- Bob Carpenter
  Columbia Uni, Dept of Statistics

Attachment: stan_agrad_ALPHA.tgz
Description: GNU Zip compressed data