find_perm.h File Reference

#include "coeffs/coeffs.h"
#include "polys/matpol.h"

Go to the source code of this file.

Functions
matrix	ma_ApplyPermForMap (const matrix to_map, const ring preimage_r, const ideal image, const ring image_r, const nMapFunc nMap)
	helper function for maMapIdeal mapping ideal/matrix/module for the case of a permutation: maps the ideal/module/matrix to_map via the map from preimage_r with image image and mapping of coefficients via nMap (or return NULL) More...

Function Documentation

ma_ApplyPermForMap()

matrix ma_ApplyPermForMap	(	const matrix	to_map,
		const ring	preimage_r,
		const ideal	image,
		const ring	image_r,
		const nMapFunc	nMap
	)

helper function for maMapIdeal mapping ideal/matrix/module for the case of a permutation: maps the ideal/module/matrix to_map via the map from preimage_r with image image and mapping of coefficients via nMap (or return NULL)

Definition at line 69 of file find_perm.cc.

{
  if ((rPar(preimage_r)>0)||(rPar(image_r)>0)) return NULL; /* not applicable */
  int *perm=find_perm_for_map(preimage_r,image_r,image);
  if (perm==NULL) return NULL; /* could not find permutation */
  int C=to_map->cols();
  int R=to_map->rows();
  matrix m=mpNew(R,C);
  for (int i=R*C-1;i>=0;i--)
  {
    if (to_map->m[i]!=NULL)
    {
      m->m[i]=p_PermPoly(to_map->m[i],perm,preimage_r,image_r, nMap,NULL,0);
      p_Test(m->m[i],image_r);
    }
  }
  ideal ii=(ideal)m;
  ii->rank=((ideal)to_map)->rank;
  omFreeSize(perm,(preimage_r->N+1)*sizeof(int));
  return m;
}