Am 23.12.2014 um 04:29 schrieb Aaron Meurer:
[...] we have a special subclass of Symbol called Dummy
which creates new objects each time. I think the way it's implemented
is that the Dummy class has an internal counter that is incremented
each time an instance is created and used for equality co
On Sat, Dec 20, 2014 at 9:39 PM, Richard Fateman wrote:
> Thanks for the detailed explanation. I hope my further elaboration
> will be of some use...
>
>
> On Friday, December 19, 2014 8:02:04 PM UTC-8, Aaron Meurer wrote:
>>
>> On Thu, Dec 18, 2014 at 5:47 PM, Richard Fateman wrote:
>> > Please
On Sunday, December 21, 2014 7:39:37 AM UTC+3, Richard Fateman wrote:
>
> It seems to me this can cause problems if, inside some scope, you need
> to create or manipulate SymPy symbols for local
> usage. (It can be done by "gensym" in Lisp, so maybe you do this?)
>
You can use Dummy:
x1 = Dummy
Thanks for the detailed explanation. I hope my further elaboration
will be of some use...
On Friday, December 19, 2014 8:02:04 PM UTC-8, Aaron Meurer wrote:
>
> On Thu, Dec 18, 2014 at 5:47 PM, Richard Fateman > wrote:
> > Please forgive me if this is off track -- I've never used assumptions i
I got around to making a very lightweight Proof-of-Concept
in https://github.com/sympy/sympy/pull/8664
On Friday, December 19, 2014 10:02:04 PM UTC-6, Aaron Meurer wrote:
>
> On Thu, Dec 18, 2014 at 5:47 PM, Richard Fateman > wrote:
> > Please forgive me if this is off track -- I've never used
On Thu, Dec 18, 2014 at 5:47 PM, Richard Fateman wrote:
> Please forgive me if this is off track -- I've never used assumptions in
> sympy, and
> don't know much about sympy implementation.
>
> But here's a problem that has come up in a number of other computer algebra
> system
> that are (in some
On Friday, December 19, 2014 2:47:44 AM UTC+3, Richard Fateman wrote:
>
> Please forgive me if this is off track -- I've never used assumptions in
> sympy, and
> don't know much about sympy implementation.
>
Actually, we have two:
sympy/core/assumptions.py (old one)
and
sympy/assumptions/ (new)
Please forgive me if this is off track -- I've never used assumptions in
sympy, and
don't know much about sympy implementation.
But here's a problem that has come up in a number of other computer algebra
system
that are (in some way) linked to a programming language.
If you say something about
I agree that the new assumptions can be cumbersome. We should
definitely keep support for old style assumptions syntax (Symbol('x',
positive=True). The downside to it is that that doesn't work for
expressions. Your idea, of basically tying assumptions to an
expression, is interesting. How would Gua
This proposal is a little far-reaching, but I think it solves some real
issues with the ease of use of refine and provides a reasonable way forward
for typed symbols.
The problem with refine is that:
(1) It's wordy. Assumptions on symbols are succinct and easy.
(2) It requires explicit invocatio
10 matches
Mail list logo
