Solution 2: Linear Lexicographical Lead rewriting systems

The same problem can also be tackled by the linear-lead routines. In the case, when all variables are substituted by constants, all intermediate results (generated during ll_red_nf_redsb/ll_red_nf_noredsb) are constant. In general, we consider the overhead of generating the encoding $ d$ as small, since it consists of very few, tiny ZDD operations only (and some Python overhead in the quite general ll_encode).
d=ll_encode([x+cx,y+cy])
ll_red_nf_noredsb(f,d)
Since the tails of the polynomials in the rewriting system consist of constants only, this forms also a reduced Gröbner basis. Therefore, you may just call
ll_red_nf_redsb(f,d)
This is assumed to be the fastest way.



2010-09-29