4.8.9 Custom Term-Orderings |
>
on the set of the terms of a polynomial ring
in n variables corresponds to a (not uniquely determined)
array (u_1,...,u_s)
of vectors of the real vector
space R^n. More precisely if a = (a_1,
... ,a_n) and b = (b_1, ... ,b_n)
are the n-tuples of the exponents of two terms t and t', then
Example |
-- The following CoCoA command defines S to be a polynomial ring and -- orders the terms of S using the term-ordering corresponding to the -- vectors (1,1,0,0),(0,-1,0,0),(0,0,1,1),(0,0,0,-1): Use S ::= Q[x,y,z,t], Ord( Mat([[1, 1, 0, 0], [0,-1, 0, 0], [0, 0, 1, 1], [0, 0, 0,-1]]) ); |