Singular

7.8.6 rightstd (letterplace)

Syntax:

rightstd( ideal_expression); rightstd( module_expression);

Type:

ideal or module

Purpose:

Compute a right Groebner basis of the set of generators of the input ideal/module.

Note: It is effective also in factor rings.

Example:

LIB "freegb.lib"; ring r = 0,(x,z),dp; ring R = freeAlgebra(r,7); ideal I = z, x*z, x*x*z; rightstd(I); // a right GB of I in K<x,z> ==> _[1]=z ==> _[2]=x*z ==> _[3]=x*x*z qring Q = twostd(x*z); // now we change to the factor algebra modulo x*z ideal I = imap(R,I); rightstd(I); // a right GB in a factor algebra ==> _[1]=z reduce(I,twostd(0)); // an explanation for the latter ==> _[1]=z ==> _[2]=0 ==> _[3]=0