/**
 * Eliminates all the equalities in a set of constraints and returns the set of
 * constraints defining a full-dimensional polyhedron, such that there is a
 * bijection between integer points of the original polyhedron and these of the
 * resulting (projected) polyhedron).
 * If VL is set to NULL, this funciton allocates it. Else, it assumes that
 * (*VL) points to a matrix of the right size.
 * <p> The following things are done: 
 * <ol>
 * <li> remove equalities involving only parameters, and remove as many
 *      parameters as there are such equalities. From that, the list of
 *      eliminated parameters <i>elimParms</i> is built.
 * <li> remove equalities that involve variables. This requires a compression
 *      of the parameters and of the other variables that are not eliminated.
 *      The affine compresson is represented by matrix VL (for <i>validity
 *      lattice</i>) and is such that (N I 1)^T = VL.(N' I' 1), where N', I'
 *      are integer (they are the parameters and variables after compression).
 *</ol>
 *</p>
 */
void Constraints_fullDimensionize(Matrix ** M, Matrix ** C, Matrix ** VL, 
				  Matrix ** Eqs, Matrix ** ParmEqs, 
				  unsigned int ** elimVars, 
				  unsigned int ** elimParms,
				  int maxRays) {
  unsigned int i, j;
  Matrix * A=NULL, *B=NULL;
  Matrix * Ineqs=NULL;
  unsigned int nbVars = (*M)->NbColumns - (*C)->NbColumns;
  unsigned int nbParms;
  int nbElimVars;
  Matrix * fullDim = NULL;

  /* variables for permutations */
  unsigned int * permutation;
  Matrix * permutedEqs=NULL, * permutedIneqs=NULL;
  
  /* 1- Eliminate the equalities involving only parameters. */
  (*ParmEqs) = Constraints_removeParmEqs(M, C, 0, elimParms);
  /* if the polyehdron is empty, return now. */
  if ((*M)->NbColumns==0) return;
  /* eliminate the columns corresponding to the eliminated parameters */
  if (elimParms[0]!=0) {
    Constraints_removeElimCols(*M, nbVars, (*elimParms), &A);
    Matrix_Free(*M);
    (*M) = A;
    Constraints_removeElimCols(*C, 0, (*elimParms), &B);
    Matrix_Free(*C);
    (*C) = B;
    if (dbgCompParm) {
      printf("After false parameter elimination: \n");
      show_matrix(*M);
      show_matrix(*C);
    }
  }
  nbParms = (*C)->NbColumns-2;

  /* 2- Eliminate the equalities involving variables */
  /*   a- extract the (remaining) equalities from the poyhedron */
  split_constraints((*M), Eqs, &Ineqs);
  nbElimVars = (*Eqs)->NbRows;
  /*    if the polyhedron is already full-dimensional, return */
  if ((*Eqs)->NbRows==0) {
    Matrix_identity(nbParms+1, VL);
    return;
  }
  /*   b- choose variables to be eliminated */
  permutation = find_a_permutation((*Eqs), nbParms);

  if (dbgCompParm) {
    printf("Permuting the vars/parms this way: [ ");
    for (i=0; i< (*Eqs)->NbColumns-2; i++) {
      printf("%d ", permutation[i]);
    }
    printf("]\n");
  }

  Constraints_permute((*Eqs), permutation, &permutedEqs);
  Equalities_validityLattice(permutedEqs, (*Eqs)->NbRows, VL);

  if (dbgCompParm) {
    printf("Validity lattice: ");
    show_matrix(*VL);
  }
  Constraints_compressLastVars(permutedEqs, (*VL));
  Constraints_permute(Ineqs, permutation, &permutedIneqs);
  if (dbgCompParmMore) {
    show_matrix(permutedIneqs);
    show_matrix(permutedEqs);
  }
  Matrix_Free(*Eqs);
  Matrix_Free(Ineqs);
  Constraints_compressLastVars(permutedIneqs, (*VL));
  if (dbgCompParm) {
    printf("After compression: ");
    show_matrix(permutedIneqs);
  }
  /*   c- eliminate the first variables */
  assert(Constraints_eliminateFirstVars(permutedEqs, permutedIneqs));
  if (dbgCompParmMore) {
    printf("After elimination of the variables: ");
    show_matrix(permutedIneqs);
  }

  /*   d- get rid of the first (zero) columns, 
       which are now useless, and put the parameters back at the end */
  fullDim = Matrix_Alloc(permutedIneqs->NbRows,
			 permutedIneqs->NbColumns-nbElimVars);
  for (i=0; i< permutedIneqs->NbRows; i++) {
    value_set_si(fullDim->p[i][0], 1);
    for (j=0; j< nbParms; j++) {
      value_assign(fullDim->p[i][j+fullDim->NbColumns-nbParms-1], 
		   permutedIneqs->p[i][j+nbElimVars+1]);
    }
    for (j=0; j< permutedIneqs->NbColumns-nbParms-2-nbElimVars; j++) {
      value_assign(fullDim->p[i][j+1], 
		   permutedIneqs->p[i][nbElimVars+nbParms+j+1]);
    }
    value_assign(fullDim->p[i][fullDim->NbColumns-1], 
		 permutedIneqs->p[i][permutedIneqs->NbColumns-1]);
  }
  Matrix_Free(permutedIneqs);

} /* Constraints_fullDimensionize */
/**
 * Given a matrix with m parameterized equations, compress the nb_parms
 * parameters and n-m variables so that m variables are integer, and transform
 * the variable space into a n-m space by eliminating the m variables (using
 * the equalities) the variables to be eliminated are chosen automatically by
 * the function.
 * <b>Deprecated.</b> Try to use Constraints_fullDimensionize instead.
 * @param M the constraints 
 * @param the number of parameters
 * @param validityLattice the the integer lattice underlying the integer
 * solutions.
*/
Matrix * full_dimensionize(Matrix const * M, int nbParms, 
			   Matrix ** validityLattice) {
  Matrix * Eqs, * Ineqs;
  Matrix * permutedEqs, * permutedIneqs;
  Matrix * Full_Dim;
  Matrix * WVL; /* The Whole Validity Lattice (vars+parms) */
  unsigned int i,j;
  int nbElimVars;
  unsigned int * permutation, * permutationInv;
  /* 0- Split the equalities and inequalities from each other */
  split_constraints(M, &Eqs, &Ineqs);

  /* 1- if the polyhedron is already full-dimensional, return it */
  if (Eqs->NbRows==0) {
    Matrix_Free(Eqs);
    (*validityLattice) = Identity_Matrix(nbParms+1);
    return Ineqs;
  }
  nbElimVars = Eqs->NbRows;

  /* 2- put the vars to be eliminated at the first positions, 
     and compress the other vars/parms
     -> [ variables to eliminate / parameters / variables to keep ] */
  permutation = find_a_permutation(Eqs, nbParms);
  if (dbgCompParm) {
    printf("Permuting the vars/parms this way: [ ");
    for (i=0; i< Eqs->NbColumns; i++) {
      printf("%d ", permutation[i]);
    }
    printf("]\n");
  }
  permutedEqs = mpolyhedron_permute(Eqs, permutation);
  WVL = compress_parms(permutedEqs, Eqs->NbColumns-2-Eqs->NbRows);
  if (dbgCompParm) {
    printf("Whole validity lattice: ");
    show_matrix(WVL);
  }
  mpolyhedron_compress_last_vars(permutedEqs, WVL);
  permutedIneqs = mpolyhedron_permute(Ineqs, permutation);
  if (dbgCompParm) {
    show_matrix(permutedEqs);
  }
  Matrix_Free(Eqs);
  Matrix_Free(Ineqs);
  mpolyhedron_compress_last_vars(permutedIneqs, WVL);
  if (dbgCompParm) {
    printf("After compression: ");
    show_matrix(permutedIneqs);
  }
  /* 3- eliminate the first variables */
  if (!mpolyhedron_eliminate_first_variables(permutedEqs, permutedIneqs)) {
    fprintf(stderr,"full-dimensionize > variable elimination failed. \n"); 
    return NULL;
  }
  if (dbgCompParm) {
    printf("After elimination of the variables: ");
    show_matrix(permutedIneqs);
  }

  /* 4- get rid of the first (zero) columns, 
     which are now useless, and put the parameters back at the end */
  Full_Dim = Matrix_Alloc(permutedIneqs->NbRows,
			  permutedIneqs->NbColumns-nbElimVars);
  for (i=0; i< permutedIneqs->NbRows; i++) {
    value_set_si(Full_Dim->p[i][0], 1);
    for (j=0; j< nbParms; j++) 
      value_assign(Full_Dim->p[i][j+Full_Dim->NbColumns-nbParms-1], 
		   permutedIneqs->p[i][j+nbElimVars+1]);
    for (j=0; j< permutedIneqs->NbColumns-nbParms-2-nbElimVars; j++) 
      value_assign(Full_Dim->p[i][j+1], 
		   permutedIneqs->p[i][nbElimVars+nbParms+j+1]);
    value_assign(Full_Dim->p[i][Full_Dim->NbColumns-1], 
		 permutedIneqs->p[i][permutedIneqs->NbColumns-1]);
  }
  Matrix_Free(permutedIneqs);
  
  /* 5- Keep only the the validity lattice restricted to the parameters */
  *validityLattice = Matrix_Alloc(nbParms+1, nbParms+1);
  for (i=0; i< nbParms; i++) {
    for (j=0; j< nbParms; j++)
      value_assign((*validityLattice)->p[i][j], 
		   WVL->p[i][j]);
    value_assign((*validityLattice)->p[i][nbParms], 
		 WVL->p[i][WVL->NbColumns-1]);
  }
  for (j=0; j< nbParms; j++) 
    value_set_si((*validityLattice)->p[nbParms][j], 0);
  value_assign((*validityLattice)->p[nbParms][nbParms], 
	       WVL->p[WVL->NbColumns-1][WVL->NbColumns-1]);

  /* 6- Clean up */
  Matrix_Free(WVL);
  return Full_Dim;
} /* full_dimensionize */
Beispiel #3
0
void kpartition_build_level_topology(tree_t *cur_node, com_mat_t *com_mat, int N, int depth,
				     tm_topology_t *topology, int *local_vertices,
				     int *constraints, int nb_constraints,
				     double *obj_weight, double *comm_speed)
{
  com_mat_t **tab_com_mat = NULL; /* table of comunication matrix. We will have k of such comunication matrix, one for each subtree */
  int k = topology->arity[depth];
  tree_t **tab_child = NULL;
  int *partition = NULL;
  int **tab_local_vertices = NULL;
  constraint_t *const_tab = NULL;
  int i;
  verbose_level = get_verbose_level();

  /* if we are at the bottom of the tree set cur_node
   and return*/
  if ( depth == topology->nb_levels - 1 ){
    if(verbose_level>=DEBUG)
      printf("id : %d, com_mat= %p\n",local_vertices[0], (void *)com_mat->comm);
    set_node(cur_node,NULL, 0, NULL, local_vertices[0], 0, NULL, depth);
    return;
  }


  /* partition the com_matrix in k partitions*/
  partition = kpartition(topology->arity[depth], com_mat, N, constraints, nb_constraints);

  /* split the communication matrix in k parts according to the partition just found above */
  tab_com_mat = split_com_mat( com_mat, N, k, partition);

  /* split the local vertices in k parts according to the partition just found above */
  tab_local_vertices = split_vertices( local_vertices, N, k, partition);

  /* construct a tab of constraints of  size k: one for each partitions*/
  const_tab = split_constraints (constraints, nb_constraints, k, topology, depth);

  /* create the table of k nodes of the resulting sub-tree */
  tab_child = (tree_t **) CALLOC (k,sizeof(tree_t*));
  for( i = 0 ; i < k ; i++){
    tab_child[i] = (tree_t *) MALLOC(sizeof(tree_t));
  }

  /* for each child, proceeed recursively*/
  for( i = 0 ; i < k ; i++){
    tab_child[i]->id = i;
    kpartition_build_level_topology ( tab_child[i], tab_com_mat[i], N/k, depth + 1,
				      topology, tab_local_vertices[i],
				      const_tab[i].constraints, const_tab[i].length,
				      obj_weight, comm_speed);
    tab_child[i]->parent = cur_node;
  }

  /* link the node with its child */
  set_node( cur_node, tab_child, k, NULL, cur_node->id, 0, NULL, depth);

  /* FREE local data*/
  FREE(partition);
  FREE_tab_com_mat(tab_com_mat,k);
  FREE_tab_local_vertices(tab_local_vertices,k);
  FREE_const_tab(const_tab,k);
}