Top
Back: eigenvalues
Forward: syModStd
FastBack: realizationMatroids_lib
FastForward: derham_lib
Up: symodstd_lib
Top: Singular Manual
Contents: Table of Contents
Index: Index
About: About this document

D.15.19.5 symmStd

Procedure from library symodstd.lib (see symodstd_lib).

Usage:
symmStd(I,sigma,#); I ideal, sigma intvec

Assume:
size(sigma) = nvars(basering) =: n, basering has an order(sigma)-th primitive root of unity a (if char(basering) > 0) and sigma(I) = I

Return:
ideal, a standard basis of I

Note:
Assuming that the ideal I is invariant under the variable permutation sigma and the basering has an order(sigma)-th primitive root of unity the procedure uses linear transformation of variables in order to improve standard basis computation.
If char(basering) = 0 all computations are done in the polynomial ring over the smallest field extension that has an order(sigma)-th primitive root of unity.

Example:
 


Top Back: eigenvalues Forward: syModStd FastBack: realizationMatroids_lib FastForward: derham_lib Up: symodstd_lib Top: Singular Manual Contents: Table of Contents Index: Index About: About this document
            User manual for Singular version 3-1-6, Dec 2012, generated by texi2html.