[Axiom-developer] RE: Polymake needs permission to write a file

[Page, Bill]

Martin,

On Wednesday, August 24, 2005 6:23 AM you wrote:

> I wrote:
> >
> > polymake SOCKET_FILE
> > polymake HOSTNAME:PORT
> >
> 
> Yes, but I have no idea how to use sockets from an axiom domain.
> Do you? If so, go ahead and show me a simple example. I can then
> adapt the domain.

Use of sockets requires compilation of Axiom with the newest
version of GCL (2.6.7). At the present time the lisp functions
for access to sockets is not exposed to the user but doing this
would not be difficult. But in short it can not be done yet
without some lisp programming. I am planning to re-build Axiom
very soon with gcl-2.6.7 and Peter Broadbery's work on Aldor.
When that is done that I will be able to give you an example
of sockets in Axiom.

> 
> > BTW, I think there may be a problem with one of the constructors:
> >
> > $ /usr/local/polymake/bin/rand_sphere randsp.poly 2 3
> > Illegal instruction
> > $
> 
> Hm, on my machine here it works just fine... Except that I need to
> parametrize the domain, to allow for polytopes with vertices being
> floats or rational numbers.

I don't understand what you mean by "parameterize the domain". This
does not involve Axiom as such although it is called by one of your
"spad wrappers". This is just a direct call to one of the standard
polymake constructors (ref: the polymake user guide):

rand_sphere <file> <dimension> <n> [ -precision <digits> ] [ -seed <s> ]

Produce a d-dimensional polytope with n random vertices on the unit
sphere. Floating-point coordinates are used. Uniform distribution.
The default precision is set to 6 digits.

-------

On your computer if you type:

rand_sphere randsp.poly 2 3

what are the contents of the randsp.poly file?

> 
> I grepped my polymake directory for "Illegal instruction" but got
> no match. Where does this come from?
> 

This is an error message from the linux operating system indicating
that the program tried to execute an illegal machine instruction (i.e.
an instruction that was not allowed by the CPU in the particular state
that it was in). This one of several different kinds of program aborts
and is usually caused by a programming error or perhaps a compiler
error.
This problem might be solved if we could just re-compile the programs
from source code.

Regards,
Bill Page.