maps.h File Reference

#include <coeffs/coeffs.h>
#include <polys/monomials/ring.h>

Go to the source code of this file.

Functions
poly	maEval (map theMap, poly p, ring preimage_r, nMapFunc nMap, ideal s, const ring dst_r)
map	maCopy (map theMap, const ring dst_ring)
poly	maIMap (ring src_ring, ring dst_ring, poly p)
void	maFindPerm (char const *const *const preim_names, int preim_n, char const *const *const preim_par, int preim_p, char const *const *const names, int n, char const *const *const par, int nop, int *perm, int *par_perm, n_coeffType ch)
poly	pSubstPoly (poly p, int var, poly image)
ideal	idSubstPoly (ideal id, int n, poly e)
poly	p_MinPolyNormalize (poly p, const ring r)
int	maMaxDeg_P (poly p, ring preimage_r)
int	maMaxDeg_Ma (ideal a, ring preimage_r)

Function Documentation

ideal idSubstPoly	(	ideal	id,
		int	n,
		poly	e
	)

Definition at line 420 of file maps_ip.cc.

{

#ifdef HAVE_PLURAL
  if (rIsPluralRing(currRing))
  {
    int k=MATROWS((matrix)id)*MATCOLS((matrix)id);
    ideal res=(ideal)mpNew(MATROWS((matrix)id),MATCOLS((matrix)id));
    res->rank = id->rank;
    for(k--;k>=0;k--)
    {
      res->m[k]=pSubst(pCopy(id->m[k]),n,e);
    }
    return res;
  }
#endif
  map theMap=(map)idMaxIdeal(1);
  theMap->preimage=NULL;
  pDelete(&(theMap->m[n-1]));
  theMap->m[n-1]=pCopy(e);

  leftv v=(leftv)omAlloc0Bin(sleftv_bin);
  sleftv tmpW;
  memset(&tmpW,0,sizeof(sleftv));
  tmpW.rtyp=IDEAL_CMD;
  tmpW.data=id;
  if (maApplyFetch(MAP_CMD,theMap,v,&tmpW,currRing,NULL,NULL,0,
                          n_SetMap(currRing->cf, currRing->cf)))
  {
    WerrorS("map failed");
    v->data=NULL;
  }
  ideal res=(ideal)(v->data);
  idDelete((ideal *)(&theMap));
  omFreeBin((ADDRESS)v, sleftv_bin);
  return res;
}

map maCopy	(	map	theMap,
		const ring	dst_ring
	)

Definition at line 38 of file maps.cc.

{
  int i;
  map m=(map)idInit(IDELEMS(theMap),0);
  for (i=IDELEMS(theMap)-1; i>=0; i--)
      m->m[i] = p_Copy(theMap->m[i],r);
  m->preimage=omStrDup(theMap->preimage);
  return m;
}

poly maEval	(	map	theMap,
		poly	p,
		ring	preimage_r,
		nMapFunc	nMap,
		ideal	s,
		const ring	dst_r
	)

Definition at line 121 of file maps.cc.

{
  poly result = NULL;
  int i;

//  for(i=1; i<=preimage_r->N; i++)
//  {
//    pTest(theMap->m[i-1]);
//  }
//  while (p!=NULL)
//  {
//    poly q=maEvalMonom(theMap,p,preimage_r,s);
//    result = pAdd(result,q);
//    pIter(p);
//  }
  if (p!=NULL)
  {
    int l = pLength(p)-1;
    poly* monoms;
    if (l>0)
    {
      monoms = (poly*) omAlloc(l*sizeof(poly));

      for (i=0; i<l; i++)
      {
        monoms[i]=maEvalMonom(theMap,p,preimage_r,s, nMap, dst_r);
        pIter(p);
      }
    }
    result=maEvalMonom(theMap,p,preimage_r,s, nMap, dst_r);
    if (l>0)
    {
      for(i = l-1; i>=0; i--)
      {
        result=p_Add_q(result, monoms[i], dst_r);
      }
      omFreeSize((ADDRESS)monoms,l*sizeof(poly));
    }

    assume(dst_r != NULL);
    assume(dst_r->cf != NULL);

    if (nCoeff_is_algExt(dst_r->cf))
      result = p_MinPolyNormalize(result, dst_r);
  }
  return result;
}

void maFindPerm	(	char const *const *const	preim_names,
		int	preim_n,
		char const *const *const	preim_par,
		int	preim_p,
		char const *const *const	names,
		int	n,
		char const *const *const	par,
		int	nop,
		int *	perm,
		int *	par_perm,
		n_coeffType	ch
	)

Definition at line 169 of file maps.cc.

{
  int i,j;
  /* find correspondig vars */
  for (i=0; i<preim_n; i++)
  {
    for(j=0; j<n; j++)
    {
      if (strcmp(preim_names[i],names[j])==0)
      {
        if (BVERBOSE(V_IMAP))
          Print("// var %s: nr %d -> nr %d\n",preim_names[i],i+1,j+1);
        /* var i+1 from preimage ring is var j+1  (index j+1) from image ring */
        perm[i+1]=j+1;
        break;
      }
    }
    if ((perm[i+1]==0)&&(par!=NULL)
        // do not consider par of Fq
         && (ch!=n_GF))
    {
      for(j=0; j<nop; j++)
      {
        if (strcmp(preim_names[i],par[j])==0)
        {
          if (BVERBOSE(V_IMAP))
            Print("// var %s: nr %d -> par %d\n",preim_names[i],i+1,j+1);
          /* var i+1 from preimage ring is par j+1 (index j) from image ring */
          perm[i+1]=-(j+1);
        }
      }
    }
  }
  if (par_perm!=NULL)
  {
    for (i=0; i<preim_p; i++)
    {
      for(j=0; j<n; j++)
      {
        if (strcmp(preim_par[i],names[j])==0)
        {
          if (BVERBOSE(V_IMAP))
            Print("// par %s: par %d -> nr %d\n",preim_par[i],i+1,j+1);
          /*par i+1 from preimage ring is var j+1  (index j+1) from image ring*/
          par_perm[i]=j+1;
          break;
        }
      }
      if ((par!=NULL) && (par_perm[i]==0))
      {
        for(j=0; j<nop; j++)
        {
          if (strcmp(preim_par[i],par[j])==0)
          {
            if (BVERBOSE(V_IMAP))
              Print("// par %s: nr %d -> par %d\n",preim_par[i],i+1,j+1);
            /*par i+1 from preimage ring is par j+1 (index j) from image ring */
            par_perm[i]=-(j+1);
          }
        }
      }
    }
  }
}

poly maIMap	(	ring	src_ring,
		ring	dst_ring,
		poly	p
	)

int maMaxDeg_Ma	(	ideal	a,
		ring	preimage_r
	)

Definition at line 258 of file maps.cc.

{
  int i,j;
  int N = preimage_r->N;
  poly p;
  int *m=(int *)omAlloc0(N*sizeof(int));

  for (i=MATROWS(a)*MATCOLS(a)-1;i>=0;i--)
  {
    p=a->m[i];
    //pTest(p); // cannot test p because it is from another ring
    while(p!=NULL)
    {
      for(j=N-1;j>=0;j--)
      {
        m[j]=si_max(m[j],(int)p_GetExp( p,j+1,preimage_r));
        if (m[j]>=MAX_MAP_DEG)
        {
          i=MAX_MAP_DEG;
          goto max_deg_fertig_id;
        }
      }
      pIter(p);
    }
  }
  i=m[0];
  for(j=N-1;j>0;j--)
  {
    i=si_max(i,m[j]);
  }
max_deg_fertig_id:
  omFreeSize((ADDRESS)m,N*sizeof(int));
  return i;
}

int maMaxDeg_P	(	poly	p,
		ring	preimage_r
	)

Definition at line 296 of file maps.cc.

{
  int i,j;
  int N = preimage_r->N;
  int *m=(int *)omAlloc0(N*sizeof(int));

//  pTest(p);
  while(p!=NULL)
  {
    for(j=N-1;j>=0;j--)
    {
      m[j]=si_max(m[j],(int)p_GetExp(p,j+1,preimage_r));
      if (m[j]>=MAX_MAP_DEG)
      {
        i=MAX_MAP_DEG;
        goto max_deg_fertig_p;
      }
    }
    pIter(p);
  }
  i=m[0];
  for(j=N-1;j>0;j--)
  {
    i=si_max(i,m[j]);
  }
max_deg_fertig_p:
  omFreeSize((ADDRESS)m,N*sizeof(int));
  return i;
}

poly p_MinPolyNormalize	(	poly	p,
		const ring	r
	)

Definition at line 328 of file maps.cc.

{
  const coeffs C = r->cf;
  number one = n_Init(1, C);
  spolyrec rp;

  poly q = &rp;

  while (p != NULL)
  {
    // this returns 0, if p == MinPoly
    number product = n_Mult(p_GetCoeff(p, r), one, C);
    if ((product == NULL)||(n_IsZero(product, C)))
    {
      p_LmDelete(&p, r);
    }
    else
    {
      p_SetCoeff(p, product, r);
      pNext(q) = p;
      q = p;
      p = pNext(p);
    }
  }
  pNext(q) = NULL;
  n_Delete(&one, C);
  return rp.next;
}

poly pSubstPoly	(	poly	p,
		int	var,
		poly	image
	)

Definition at line 365 of file maps_ip.cc.

{
  if (p==NULL) return NULL;
#ifdef HAVE_PLURAL
  if (rIsPluralRing(currRing))
  {
    return pSubst(pCopy(p),var,image);
  }
#endif
  map theMap=(map)idMaxIdeal(1);
  theMap->preimage=NULL;
  pDelete(&(theMap->m[var-1]));
  theMap->m[var-1]=pCopy(image);

  poly res=NULL;
#ifdef FAST_MAP
  if (pGetComp(p)==0)
  {
    ideal src_id=idInit(1,1);
    src_id->m[0]=p;

    char *tmp = theMap->preimage;
    theMap->preimagei=(char*)1L; // map gets 1 as its rank (as an ideal)
    ideal res_id=fast_map(src_id,currRing,(ideal)theMap,currRing);
    theMap->preimage=tmp; // map gets its preimage back

    res=res_id->m[0];
    res_id->m[0]=NULL; idDelete(&res_id);
    src_id->m[0]=NULL; idDelete(&src_id);
  }
  else
#endif
  {
    sleftv tmpW;
    memset(&tmpW,0,sizeof(sleftv));
    tmpW.rtyp=POLY_CMD;
    tmpW.data=p;
    leftv v=(leftv)omAlloc0Bin(sleftv_bin);
    if (maApplyFetch(MAP_CMD,theMap,v,&tmpW,currRing,NULL,NULL,0,
                            n_SetMap(currRing->cf, currRing->cf)))
    {
      WerrorS("map failed");
      v->data=NULL;
    }
    res=(poly)(v->data);
    omFreeBin((ADDRESS)v, sleftv_bin);
  }
  idDelete((ideal *)(&theMap));
  return res;
}