On Sunday 07 September 2008, mmarco wrote:
> Martin Albrecht ha escrito:
> > Hi Miguel,
> >
> > can you be convinced to work on it some more?
>
> Sure
>
Hi there,
> I will take a look at it, considering your comments. The reason why i
> didn't use most of what you suggested is because i didn't know about
> it (i am new to sage). I will take a look at it and try to write a
> revised version in the next days.
Thanks, feel free to ask questions that arise during the process :-)
> > 4) Injecting a variable into the global namespace in a function
> > ('defining a') is bad practice, IMHO. It should be avoided. It is better
> > to create a variable in the local scope and pass it on to eval.
>
> the reason why i did that is because i couldn't find a way to create a
> variable that has the same name as the one used in the singular
> polynomial. I agree it is not a desirable thing to create a variable
> in the process, but it was the best i could find. How can i implement
> what you suggest?
Yes :-) sage_eval (and eval) accept additional parameters which are
dictionaries with name object mappings:
sage: K = NumberField(x^2 + 1,'a')
sage: sage_eval("a+1",{K.variable_name():K.gen()})
a + 1
So you don't need to create such a variable, just pass in the correct mapping
to the evaluation function.
Cheers,
Martin
--
name: Martin Albrecht
_pgp: http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x8EF0DC99
_www: http://www.informatik.uni-bremen.de/~malb
_jab: [EMAIL PROTECTED]
--~--~---------~--~----~------------~-------~--~----~
To post to this group, send email to sage-devel@googlegroups.com
To unsubscribe from this group, send email to [EMAIL PROTECTED]
For more options, visit this group at http://groups.google.com/group/sage-devel
URLs: http://www.sagemath.org
-~----------~----~----~----~------~----~------~--~---
