[GiNaC-devel] New .is_polynomial() method.

[Chris Dams]

Dear all,

I have added a method .is_polynomial() to GiNaC. Using 
.info(info_flags::polynomial) is not sufficient because in that case one 
cannot distinguish an expression that may be a polynomial in a variable 
but nog in another. Example: x*y*sin(y) is a polynomial in x but not in y.
Hence (x*y*sin(y)).is_polynomial(x) returns true but 
(x*y*sin(y)).is_polynomial(lst(x,y)) returns false. I also patched the 
tutorial.

Best,
Chris