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D.15.11.17 makePDivisor

Procedure from library divisors.lib (see divisors_lib).

Usage:
makePDivisor(L); L = list.

Assume:
L is a list of tuples of a integral polyhedron and a divisor such that all polyhedra have the same tail cone.

Return:
a pdivisor on X

Theory:
Represents an polyhedral formal sum of divisors.

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));
intmat M[4][4]= 1,4,0,0,
1,0,3,0,
0,0,0,2,
1,1,1,1;
polytope PP = polytopeViaPoints(M);
makePDivisor(list(list(PP,A),list(PP,B)));
==> tail=<cone>
==> summands=<list>