Re: [fricas-devel] Re: [Axiom-developer] Am I posing this solve problem wrong?

[Bill Page]

On Tue, May 6, 2008 at 11:43 AM, Martin Rubey wrote:
>
> "Bill Page" <address@hidden> writes:
>
>> I have been thinking specifically about the algorithms that the Axiom
>> interpreter uses to do type inference and function selection. Some part of
>> the behavior is "hard coded" into the interpreter and not easy to change,
>> but a large part of it depends on interaction with the design of the Axiom
>> library, i.e. the coercions and other operations that are exported by exposed
>> domains. It seems to me that in many cases not enough attention has been
>> paid to "tuning" the Axiom library so that the Axiom interpreter produces
>> fewer surprises for the new user.
>
> Some time ago I posted a question in exactly this direction (something
> like "why doesn't HOAGG R export
> coerce: % -> List R and coerce: List R -> %).
>
> I can only guess that one answer (which I didn't get, but I give myself)
> is optimization: coercion done by the library *might* be relatively slow.
>

As I said in the previous thread, I think your idea is a good one.

I think you are probably being too generous to the developers. I doubt
that any such consideration of optimization was ever applied. I expect
that the detailed coding in the Axiom interpreter and the coercions
supplied (or not) by the Axiom library are merely artifacts of the
constraints to the original Axiom development process.

> However, I'm quite sure it would make a lot of sense to replace the contents
> of i-coerce by appropriate definitions in the algebra.
>

+1 Yes!

> Exploration here is very very welcome -- and in FriCAS also relatively
> painless, one only has to keep in mind that changes at this level usually
> make complete recompilation of the algebra necessary.
>
> Of course, the insights will be valuable for all three projects.
>

Agreed.

Regards,
Bill Page.