Home Online Manual
Top
Back: normalForm
Forward: globalSections
FastBack:
FastForward:
Up: divisors_lib
Top: Singular Manual
Contents: Table of Contents
Index: Index
About: About this document

D.15.11.6 isEqualDivisor

Procedure from library divisors.lib (see divisors_lib).

Usage:
isEqualDivisor(A,B); A = divisor, B = divisor.

Assume:
A and B are divisors on X.

Return:
int 0 or 1, checks equality of A and B.

Theory:
The procedure will compute the normal forms of A and B and compare.

Example:
 
LIB "divisors.lib";
==> Welcome to polymake version
==> Copyright (c) 1997-2015
==> Ewgenij Gawrilow, Michael Joswig (TU Darmstadt)
==> http://www.polymake.org
ring r=31991,(x,y,z),dp;
ideal I = y^2*z - x*(x-z)*(x+3*z);
qring Q = std(I);
divisor A = makeDivisor(ideal(x,z),ideal(1));
divisor B = makeDivisor(ideal(x,y),ideal(1));
divisor D = (A+B)+multdivisor(-1,B);
isEqualDivisor(A,D);
==> 1