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D.15.13.15 multformaldivisor

Procedure from library divisors.lib (see divisors_lib).

Usage:
multformaldivisor(n ,A); A*n; n = integer, A = formaldivisor.

Assume:
n is an integer and A is a formal divisor on X.

Return:
a formal divisor on X

Theory:
The procedure will multiply the formal sum with n.

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));
formaldivisor fE= makeFormalDivisor(list(list(-5,A),list(2,B)));
fE*2;
==> -10*( (z,x) - (1) )
==> +4*( (y,x) - (1) )
==>