7.10.4.11 setLetterplaceAttributes

Usage:

setLetterplaceAttributes(R, d, b); R a ring, b,d integers

Return:

ring with special attributes set

Purpose:

sets attributes for a letterplace ring:
'isLetterplaceRing' = 'lV' = b, 'uptodeg' = d, where 'uptodeg' stands for the degree bound,
'lV' for the number of variables in the block 0.

Note:

Activate the resulting ring by using setring

LIB "freegb.lib";
ring r = 0,(x(1),y(1),x(2),y(2),x(3),y(3),x(4),y(4)),dp;
def R = setLetterplaceAttributes(r, 4, 2); setring R;
lpVarBlockSize(R);
==> 2
lieBracket(x(1),y(1),2);
==> y(1)*x(2)*x(3)-2*x(1)*y(2)*x(3)+x(1)*x(2)*y(3)