Thank you.

On Friday, March 27, 2015 at 9:55:21 PM UTC+2, Aaron Meurer wrote:
>
> It looks like Poly.from_dict will do it: 
>
> In [6]: p = Poly(6*x**4*y**5 + 3*x*y**2,y,x) 
>
> In [7]: p.as_dict() 
> Out[7]: {(2, 1): 3, (5, 4): 6} 
>
> In [8]: p.from_dict(p.as_dict(), y, x) 
> Out[8]: Poly(6*y**5*x**4 + 3*y**2*x, y, x, domain='ZZ') 
>
> The order of the generators is the same as the order in the Poly. I 
> don't remember if there is a better method on Poly for reordering 
> generators, but in the above example Poly(p, x, y) will reorder them. 
>
> Aaron Meurer 
>
>
> On Fri, Mar 27, 2015 at 2:50 PM, Paul Royik <distan...@gmail.com 
> <javascript:>> wrote: 
> > Suppose I have following polynomial: 
> > poly= Poly(6*x**4*y**5 + 3*x*y**2,y,x) 
> > 
> > It's dictionary is 
> > poly.as_dict() # {(5, 4): 6, (2, 1): 3} 
> > 
> > 
> > How can I restore poly from dict? 
> > How do I know that (5, 4) - > (y, x) ? 
> > poly.free_symbols is set, so it is unordered. 
> > 
> > Is there any way to fetch that from Poly? 
> > 
> > One way I think is following: 
> > 
> > variables = [x,y] 
> > poly= Poly(6*x**4*y**5 + 3*x*y**2,variables) 
> > 
> > #(5, 4) - > variables 
> > 
> > 
> > And next question: how are coeffcients are ordered? Can I change order? 
> > order keyword throws exception... 
> > 
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