Re: Two bugs (2.0.16 on Linux/Alpha)

[Igor Schein <igor@txc.com>]

On Thu, Jul 29, 1999 at 06:45:20PM -0400, Matias Atria (F. de Ciencias Depto Matematicas) wrote:
> 
> My apologies if someone reported this before (especially the first problem
> below), but I have not followed this list with much attention in the last
> weeks.
> 
> I'm running...
>                     GP/PARI CALCULATOR Version 2.0.16 (beta)
>                        Alpha running linux 64-bit version
>                 (readline v2.2 enabled, extended help available)
> 
> ...and found two bugs.
> 
> ? matrix(1000,5000,i,j,cos(0.5*i*j))
>   ***   user interrupt after 1031099962854h, 339 ms.
>                              ^^^^^^^^^^^^^^^^^^^^^^
> (I obviously did not wait 1e9 years to interrupt it) The same thing happens
> whenever I use the timer.

I noticed this one too on Alpha.  This only happens for dynamic binary,
so you should run Configure -s to default to static binary.  I didn't
bother looking at it because I prefer static binaries anyway. 

> 
> ? allocatemem(256000000)
> ? matrix(1000,5000,i,j,cos(0.5*i*j))
>   ***   the PARI stack overflows !!!
> 
>   ***   Warning: doubling stack size; new stack = 512000000.
> 
> I repeated this with a stack of 800Mb and it gave me the same problem. I
> cannot imagine how PARI could need such a big amount of memory for such a
> simple calculation. Is it a GC problem?

As it is now, PARI is not the best package for matrix operations.
It has improved since, for example, version 2.0.9, but still it's
far away from where it could eventually be.  It's not on the immediate
TODO list, but Karim will tell you whether it's planned for remote future.

Igor