On Friday 12 October 2007 15:52, Nils Bruin wrote:
> Both the poly.coefficients({x:1,y:2}) and poly.coefficients(x=1,y=2)
> seem confusing to me (the latter one downright scary. Exponents and
> variable names have no business being on opposite sides of an equality
> sign).
Yes, I agree, mathematically it appears risky.
> In mathematical terms, what you want to do is view the
> polynomial ring k[x,y,z] as the ring k[z][x,y] and ask for the
> coefficient of the monomial x*y^2.
> Wouldn't it be clearer to have a call like
> poly.polynomial_coefficient({z},x*y^2) ?
I think this confuses me. What is the "{z}" indicating?
Suppose I had a poly ring with 19 variables and one of them was named "y".
How would I get the coefficient for y^0 in your syntax? (That is, the
constant term in k[y][...].) This is the sticking point in what is currently
implemented.
--
Joel
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