D.15.1.42 arrChambers

Usage:

arrChambers(A); arr A

Return:

[int] The number of chambers of an arrangement, which is equal to the evaluation of the Poincare polynomial at 1.

LIB "arr.lib";
ring R = 0,(x,y),dp;
arr A = ideal(x,y,x+y-1);
arrChambers(A);
==> 7