Home Online Manual
Top
Back: integral
Forward: printSheaf
FastBack:
FastForward:
Up: schubert_lib
Top: Singular Manual
Contents: Table of Contents
Index: Index
About: About this document

D.5.17.9 makeSheaf

Procedure from library schubert.lib (see schubert_lib).

Usage:
makeSheaf(V,ch); V variety, ch poly

Return:
sheaf

Theory:
create a sheaf on an abstract variety, and its Chern character is the polynomial ch.

Example:
 
LIB "schubert.lib";
variety X;
X.dimension = 4;
ring r = 0,(c(1..2),d(1..3)),wp(1..2,1..3);
setring r;
X.baseRing = r;
poly c = 1 + c(1) + c(2);
poly ch = 2 + logg(c,4);
sheaf S = makeSheaf(X,ch);
S;
==> A sheaf of rank  2
==> 
See also: printSheaf; rankSheaf.