Home Online Manual
Top
Back: rightNF
Forward: moduloSlim
FastBack: ncpreim_lib
FastForward: perron_lib
Up: nctools_lib
Top: Singular Manual
Contents: Table of Contents
Index: Index
About: About this document
7.7.15.0. rightModulo
Procedure from library nctools.lib (see nctools_lib).

Usage:
rightModulo(M,N); M,N are ideals/modules

Purpose:
compute a right representation of the module (M+N)/N

Return:
module

Assume:
M,N are presentation matrices for right modules

Example:
 
LIB "nctools.lib";
LIB "ncalg.lib";
def A = makeUsl(2);
setring A;
option(redSB);
option(redTail);
ideal I = e2,f2,h2-1;
I = twostd(I);
print(matrix(I));
==> h2-1,fh-f,eh+e,f2,2ef-h-1,e2
ideal E  = std(e);
ideal TL = e,h-1; // the result of left modulo
TL;
==> TL[1]=e
==> TL[2]=h-1
ideal T = rightModulo(E,I);
T = rightStd(T+I);
T = rightStd(rightNF(T,I)); // make the output canonic
T;
==> T[1]=h+1
==> T[2]=e