static ppl_Constraint_t
cloog_matrix_to_ppl_constraint (CloogMatrix *matrix, int row)
{
  int j;
  ppl_Constraint_t cstr;
  ppl_Coefficient_t coef;
  ppl_Linear_Expression_t expr;
  ppl_dimension_type dim = matrix->NbColumns - 2;

  ppl_new_Coefficient (&coef);
  ppl_new_Linear_Expression_with_dimension (&expr, dim);

  for (j = 1; j < matrix->NbColumns - 1; j++)
    {
      ppl_assign_Coefficient_from_mpz_t (coef, matrix->p[row][j]);
      ppl_Linear_Expression_add_to_coefficient (expr, j - 1, coef);
    }

  ppl_assign_Coefficient_from_mpz_t (coef,
				     matrix->p[row][matrix->NbColumns - 1]);
  ppl_Linear_Expression_add_to_inhomogeneous (expr, coef);
  ppl_delete_Coefficient (coef);

  if (value_zero_p (matrix->p[row][0]))
    ppl_new_Constraint (&cstr, expr, PPL_CONSTRAINT_TYPE_EQUAL);
  else
    ppl_new_Constraint (&cstr, expr, PPL_CONSTRAINT_TYPE_GREATER_OR_EQUAL);

  ppl_delete_Linear_Expression (expr);
  return cstr;
}
Пример #2
0
/* 
 * Return the component of 'p' with minimum non-zero absolute value. 'index'
 * points to the component index that has the minimum value. If no such value
 * and index is found, Value 1 is returned.
 */
void Vector_Min_Not_Zero(Value *p,unsigned length,int *index,Value *min)
{
  Value aux;
  int i;
  
  
  i = First_Non_Zero(p, length);
  if (i == -1) {
    value_set_si(*min,1);
    return;
  }
  *index = i;
  value_absolute(*min, p[i]);
  value_init(aux);
  for (i = i+1; i < length; i++) {
    if (value_zero_p(p[i]))
      continue;
    value_absolute(aux, p[i]);
    if (value_lt(aux,*min)) {
      value_assign(*min,aux);
      *index = i;
    }  
  }
  value_clear(aux);
} /* Vector_Min_Not_Zero */
Пример #3
0
static Matrix *Polyhedron2standard_form(Polyhedron *P, Matrix **T)
{
    int i, j;
    int rows;
    unsigned dim = P->Dimension;
    Matrix *M2;
    Matrix *H, *U;
    Matrix M;

    assert(P->NbEq == 0);
    Polyhedron_Remove_Positivity_Constraint(P);
    for (i = 0; i < P->NbConstraints; ++i)
	assert(value_zero_p(P->Constraint[i][1+dim]));

    Polyhedron_Matrix_View(P, &M, P->NbConstraints);
    H = standard_constraints(&M, 0, &rows, &U);
    *T = homogenize(U);
    Matrix_Free(U);

    M2 = Matrix_Alloc(rows, 2+dim+rows);

    for (i = dim; i < H->NbRows; ++i) {
	Vector_Copy(H->p[i], M2->p[i-dim]+1, dim);
	value_set_si(M2->p[i-dim][1+i], -1);
    }
    for (i = 0, j = H->NbRows-dim; i < dim; ++i) {
	if (First_Non_Zero(H->p[i], i) == -1)
	    continue;
	Vector_Oppose(H->p[i], M2->p[j]+1, dim);
	value_set_si(M2->p[j][1+j+dim], 1);
	++j;
    }
    Matrix_Free(H);
    return M2;
}
Пример #4
0
enum lp_result PL_polyhedron_opt(Polyhedron *P, Value *obj, Value denom,
				enum lp_dir dir, Value *opt)
{
    int i;
    int first = 1;
    Value val, d;
    enum lp_result res = lp_empty;

    POL_ENSURE_VERTICES(P);
    if (emptyQ(P))
	return res;

    value_init(val);
    value_init(d);
    for (i = 0; i < P->NbRays; ++ i) {
	Inner_Product(P->Ray[i]+1, obj, P->Dimension+1, &val);
	if (value_zero_p(P->Ray[i][0]) && value_notzero_p(val)) {
	    res = lp_unbounded;
	    break;
	}
	if (value_zero_p(P->Ray[i][1+P->Dimension])) {
	    if ((dir == lp_min && value_neg_p(val)) ||
		(dir == lp_max && value_pos_p(val))) {
		res = lp_unbounded;
		break;
	    }
	} else {
	    res = lp_ok;
	    value_multiply(d, denom, P->Ray[i][1+P->Dimension]);
	    if (dir == lp_min)
		mpz_cdiv_q(val, val, d);
	    else
		mpz_fdiv_q(val, val, d);
	    if (first || (dir == lp_min ? value_lt(val, *opt) :
				          value_gt(val, *opt)))
		value_assign(*opt, val);
	    first = 0;
	}
    }
    value_clear(d);
    value_clear(val);

    return res;
}
Пример #5
0
int Vector_IsZero(Value * v, unsigned length) {
  unsigned i;
  if (value_notzero_p(v[0])) return 0;
  else {
    value_set_si(v[0], 1);
    for (i=length-1; value_zero_p(v[i]); i--);
    value_set_si(v[0], 0);
    return (i==0);
  }
}
Пример #6
0
/** 
 * Computes the intersection of two linear lattices, whose base vectors are
 * respectively represented in A and B.
 * If I and/or Lb is set to NULL, then the matrix is allocated. 
 * Else, the matrix is assumed to be allocated already. 
 * I and Lb are rk x rk, where rk is the rank of A (or B).
 * @param A the full-row rank matrix whose column-vectors are the basis for the
 * first linear lattice.
 * @param B the matrix whose column-vectors are the basis for the second linear
 * lattice.
 * @param Lb the matrix such that B.Lb = I, where I is the intersection.
 * @return their intersection.
 */
static void linearInter(Matrix * A, Matrix * B, Matrix ** I, Matrix **Lb) {
  Matrix * AB=NULL;
  int rk = A->NbRows;
  int a = A->NbColumns;
  int b = B->NbColumns;
  int i,j, z=0;

  Matrix * H, *U, *Q;
  /* ensure that the spanning vectors are in the same space */
  assert(B->NbRows==rk);
  /* 1- build the matrix 
   * (A 0 1)
   * (0 B 1)
   */
  AB = Matrix_Alloc(2*rk, a+b+rk);
  Matrix_copySubMatrix(A, 0, 0, rk, a, AB, 0, 0);
  Matrix_copySubMatrix(B, 0, 0, rk, b, AB, rk, a);
  for (i=0; i< rk; i++) {
      value_set_si(AB->p[i][a+b+i], 1);
      value_set_si(AB->p[i+rk][a+b+i], 1);
  }
  if (dbgCompParm) {
    show_matrix(AB);
  }

  /* 2- Compute its left Hermite normal form. AB.U = [H 0] */
  left_hermite(AB, &H, &Q, &U);
  Matrix_Free(AB);
  Matrix_Free(Q);
  /* count the number of non-zero colums in H */ 
  for (z=H->NbColumns-1; value_zero_p(H->p[H->NbRows-1][z]); z--);
  z++;
  if (dbgCompParm) {
    show_matrix(H);
    printf("z=%d\n", z);
  }
  Matrix_Free(H);
  /* if you split U in 9 submatrices, you have: 
   * A.U_13 = -U_33
   * B.U_23 = -U_33,
   * where the nb of cols of U_{*3} equals the nb of zero-cols of H
   * U_33 is a (the smallest) combination of col-vectors of A and B at the same
   * time: their intersection.
  */
  Matrix_subMatrix(U, a+b, z, U->NbColumns, U->NbColumns, I);
  Matrix_subMatrix(U, a, z, a+b, U->NbColumns, Lb);
  if (dbgCompParm) {
    show_matrix(U);
  }
  Matrix_Free(U);
} /* linearInter */
Пример #7
0
static __isl_give isl_mat *extract_equalities(isl_ctx *ctx, Matrix *M)
{
	int i, j;
	int n;
	isl_val *v;
	isl_mat *eq;

	n = 0;
	for (i = 0; i < M->NbRows; ++i)
		if (value_zero_p(M->p[i][0]))
			++n;

	eq = isl_mat_alloc(ctx, n, M->NbColumns - 1);
	for (i = 0; i < M->NbRows; ++i) {
		if (!value_zero_p(M->p[i][0]))
			continue;
		for (j = 0; j < M->NbColumns - 1; ++j) {
			v = isl_val_int_from_gmp(ctx, M->p[i][1 + j]);
			eq = isl_mat_set_element_val(eq, i, j, v);
		}
	}

	return eq;
}
Пример #8
0
/** Removes the equalities that involve only parameters, by eliminating some
 * parameters in the polyhedron's constraints and in the context.<p> 
 * <b>Updates M and Ctxt.</b>
 * @param M1 the polyhedron's constraints
 * @param Ctxt1 the constraints of the polyhedron's context
 * @param renderSpace tells if the returned equalities must be expressed in the
 * parameters space (renderSpace=0) or in the combined var/parms space
 * (renderSpace = 1)
 * @param elimParms the list of parameters that have been removed: an array
 * whose 1st element is the number of elements in the list.  (returned)
 * @return the system of equalities that involve only parameters.
 */
Matrix * Constraints_Remove_parm_eqs(Matrix ** M1, Matrix ** Ctxt1, 
				     int renderSpace, 
				     unsigned int ** elimParms) {
  int i, j, k, nbEqsParms =0;
  int nbEqsM, nbEqsCtxt, allZeros, nbTautoM = 0, nbTautoCtxt = 0;
  Matrix * M = (*M1);
  Matrix * Ctxt = (*Ctxt1);
  int nbVars = M->NbColumns-Ctxt->NbColumns;
  Matrix * Eqs;
  Matrix * EqsMTmp;
  
  /* 1- build the equality matrix(ces) */
  nbEqsM = 0;
  for (i=0; i< M->NbRows; i++) {
    k = First_Non_Zero(M->p[i], M->NbColumns);
    /* if it is a tautology, count it as such */
    if (k==-1) {
      nbTautoM++;
    }
    else {
      /* if it only involves parameters, count it */
      if (k>= nbVars+1) nbEqsM++;
    }
  }

  nbEqsCtxt = 0;
  for (i=0; i< Ctxt->NbRows; i++) {
    if (value_zero_p(Ctxt->p[i][0])) {
      if (First_Non_Zero(Ctxt->p[i], Ctxt->NbColumns)==-1) {
	nbTautoCtxt++;
      }
      else {
	nbEqsCtxt ++;
      }
    }
  }
  nbEqsParms = nbEqsM + nbEqsCtxt; 

  /* nothing to do in this case */
  if (nbEqsParms+nbTautoM+nbTautoCtxt==0) {
    (*elimParms) = (unsigned int*) malloc(sizeof(int));
    (*elimParms)[0] = 0;
    if (renderSpace==0) {
      return Matrix_Alloc(0,Ctxt->NbColumns);
    }
    else {
      return Matrix_Alloc(0,M->NbColumns);
    }
  }
  
  Eqs= Matrix_Alloc(nbEqsParms, Ctxt->NbColumns);
  EqsMTmp= Matrix_Alloc(nbEqsParms, M->NbColumns);
  
  /* copy equalities from the context */
  k = 0;
  for (i=0; i< Ctxt->NbRows; i++) {
    if (value_zero_p(Ctxt->p[i][0]) 
		     && First_Non_Zero(Ctxt->p[i], Ctxt->NbColumns)!=-1) {
      Vector_Copy(Ctxt->p[i], Eqs->p[k], Ctxt->NbColumns);
      Vector_Copy(Ctxt->p[i]+1, EqsMTmp->p[k]+nbVars+1, 
		  Ctxt->NbColumns-1);
      k++;
    }
  }
  for (i=0; i< M->NbRows; i++) {
    j=First_Non_Zero(M->p[i], M->NbColumns);
    /* copy equalities that involve only parameters from M */
    if (j>=nbVars+1) {
      Vector_Copy(M->p[i]+nbVars+1, Eqs->p[k]+1, Ctxt->NbColumns-1);
      Vector_Copy(M->p[i]+nbVars+1, EqsMTmp->p[k]+nbVars+1, 
		  Ctxt->NbColumns-1);
      /* mark these equalities for removal */
      value_set_si(M->p[i][0], 2);
      k++;
    }
    /* mark the all-zero equalities for removal */
    if (j==-1) {
      value_set_si(M->p[i][0], 2);
    }
  }

  /* 2- eliminate parameters until all equalities are used or until we find a
  contradiction (overconstrained system) */
  (*elimParms) = (unsigned int *) malloc((Eqs->NbRows+1) * sizeof(int));
  (*elimParms)[0] = 0;
  allZeros = 0;
  for (i=0; i< Eqs->NbRows; i++) {
    /* find a variable that can be eliminated */
    k = First_Non_Zero(Eqs->p[i], Eqs->NbColumns);
    if (k!=-1) { /* nothing special to do for tautologies */

      /* if there is a contradiction, return empty matrices */
      if (k==Eqs->NbColumns-1) {
	printf("Contradiction in %dth row of Eqs: ",k);
	show_matrix(Eqs);
	Matrix_Free(Eqs);
	Matrix_Free(EqsMTmp);
	(*M1) = Matrix_Alloc(0, M->NbColumns);
	Matrix_Free(M);
	(*Ctxt1) = Matrix_Alloc(0,Ctxt->NbColumns);
	Matrix_Free(Ctxt);
	free(*elimParms);
	(*elimParms) = (unsigned int *) malloc(sizeof(int));
	(*elimParms)[0] = 0;
	if (renderSpace==1) {
	  return Matrix_Alloc(0,(*M1)->NbColumns);
	}
	else {
	  return Matrix_Alloc(0,(*Ctxt1)->NbColumns);
	}
      }	
      /* if we have something we can eliminate, do it in 3 places:
	 Eqs, Ctxt, and M */
      else {
	k--; /* k is the rank of the variable, now */
	(*elimParms)[0]++;
	(*elimParms)[(*elimParms[0])]=k;
	for (j=0; j< Eqs->NbRows; j++) {
	  if (i!=j) {
	    eliminate_var_with_constr(Eqs, i, Eqs, j, k);
	    eliminate_var_with_constr(EqsMTmp, i, EqsMTmp, j, k+nbVars);
	  }
	}
	for (j=0; j< Ctxt->NbRows; j++) {
	  if (value_notzero_p(Ctxt->p[i][0])) {
	    eliminate_var_with_constr(Eqs, i, Ctxt, j, k);
	  }
	}
	for (j=0; j< M->NbRows; j++) {
	  if (value_cmp_si(M->p[i][0], 2)) {
	    eliminate_var_with_constr(EqsMTmp, i, M, j, k+nbVars);
	  }
	}
      }
    }
    /* if (k==-1): count the tautologies in Eqs to remove them later */
    else {
      allZeros++;
    }
  }
  
  /* elimParms may have been overallocated. Now we know how many parms have
     been eliminated so we can reallocate the right amount of memory. */
  if (!realloc((*elimParms), ((*elimParms)[0]+1)*sizeof(int))) {
    fprintf(stderr, "Constraints_Remove_parm_eqs > cannot realloc()");
  }

  Matrix_Free(EqsMTmp);

  /* 3- remove the "bad" equalities from the input matrices
     and copy the equalities involving only parameters */
  EqsMTmp = Matrix_Alloc(M->NbRows-nbEqsM-nbTautoM, M->NbColumns);
  k=0;
  for (i=0; i< M->NbRows; i++) {
    if (value_cmp_si(M->p[i][0], 2)) {
      Vector_Copy(M->p[i], EqsMTmp->p[k], M->NbColumns);
      k++;
    }
  }
  Matrix_Free(M);
  (*M1) = EqsMTmp;
  
  EqsMTmp = Matrix_Alloc(Ctxt->NbRows-nbEqsCtxt-nbTautoCtxt, Ctxt->NbColumns);
  k=0;
  for (i=0; i< Ctxt->NbRows; i++) {
    if (value_notzero_p(Ctxt->p[i][0])) {
      Vector_Copy(Ctxt->p[i], EqsMTmp->p[k], Ctxt->NbColumns);
      k++;
    }
  }
  Matrix_Free(Ctxt);
  (*Ctxt1) = EqsMTmp;
  
  if (renderSpace==0) {/* renderSpace=0: equalities in the parameter space */
    EqsMTmp = Matrix_Alloc(Eqs->NbRows-allZeros, Eqs->NbColumns);
    k=0;
    for (i=0; i<Eqs->NbRows; i++) {
      if (First_Non_Zero(Eqs->p[i], Eqs->NbColumns)!=-1) {
	Vector_Copy(Eqs->p[i], EqsMTmp->p[k], Eqs->NbColumns);
	k++;
      }
    }
  }
  else {/* renderSpace=1: equalities rendered in the combined space */
    EqsMTmp = Matrix_Alloc(Eqs->NbRows-allZeros, (*M1)->NbColumns);
    k=0;
    for (i=0; i<Eqs->NbRows; i++) {
      if (First_Non_Zero(Eqs->p[i], Eqs->NbColumns)!=-1) {
	Vector_Copy(Eqs->p[i], &(EqsMTmp->p[k][nbVars]), Eqs->NbColumns);
	k++;
      }
    }
  }
  Matrix_Free(Eqs);
  Eqs = EqsMTmp;

  return Eqs;
} /* Constraints_Remove_parm_eqs */
Пример #9
0
/* Assumes C is a linear cone (i.e. with apex zero).
 * All equalities are removed first to speed up the computation
 * in zsolve.
 */
Matrix *Cone_Hilbert_Basis(Polyhedron *C, unsigned MaxRays)
{
    unsigned dim;
    int i;
    Matrix *M2, *M3, *T;
    Matrix *CV = NULL;
    LinearSystem initialsystem;
    ZSolveMatrix matrix;
    ZSolveVector rhs;
    ZSolveContext ctx;

    remove_all_equalities(&C, NULL, NULL, &CV, 0, MaxRays);
    dim = C->Dimension;

    for (i = 0; i < C->NbConstraints; ++i)
	assert(value_zero_p(C->Constraint[i][1+dim]) ||
	       First_Non_Zero(C->Constraint[i]+1, dim) == -1);

    M2 = Polyhedron2standard_form(C, &T);
    matrix = Matrix2zsolve(M2);
    Matrix_Free(M2);

    rhs = createVector(matrix->Height);
    for (i = 0; i < matrix->Height; i++)
	rhs[i] = 0;

    initialsystem = createLinearSystem();
    setLinearSystemMatrix(initialsystem, matrix);
    deleteMatrix(matrix);

    setLinearSystemRHS(initialsystem, rhs);
    deleteVector(rhs);

    setLinearSystemLimit(initialsystem, -1, 0, MAXINT, 0);
    setLinearSystemEquationType(initialsystem, -1, EQUATION_EQUAL, 0);

    ctx = createZSolveContextFromSystem(initialsystem, NULL, 0, 0, NULL, NULL);
    zsolveSystem(ctx, 0);

    M2 = VectorArray2Matrix(ctx->Homs, C->Dimension);
    deleteZSolveContext(ctx, 1);
    Matrix_Transposition(T);
    M3 = Matrix_Alloc(M2->NbRows, M2->NbColumns);
    Matrix_Product(M2, T, M3);
    Matrix_Free(M2);
    Matrix_Free(T);

    if (CV) {
	Matrix *T, *M;
	T = Transpose(CV);
	M = Matrix_Alloc(M3->NbRows, T->NbColumns);
	Matrix_Product(M3, T, M);
	Matrix_Free(M3);
	Matrix_Free(CV);
	Matrix_Free(T);
	Polyhedron_Free(C);
	M3 = M;
    }

    return M3;
}
Пример #10
0
/*
 * Given a rational matrix 'Mat'(k x k), compute its inverse rational matrix 
 * 'MatInv' k x k.
 * The output is 1,
 * if 'Mat' is non-singular (invertible), otherwise the output is 0. Note:: 
 * (1) Matrix 'Mat' is modified during the inverse operation.
 * (2) Matrix 'MatInv' must be preallocated before passing into this function.
 */
int Matrix_Inverse(Matrix *Mat,Matrix *MatInv ) {
  
  int i, k, j, c;
  Value x, gcd, piv;
  Value m1,m2;
  Value *den;
  
  if(Mat->NbRows != Mat->NbColumns) {
   fprintf(stderr,"Trying to invert a non-square matrix !\n");
    return 0;
  }
  
  /* Initialize all the 'Value' variables */
  value_init(x);  value_init(gcd); value_init(piv);
  value_init(m1); value_init(m2);

  k = Mat->NbRows; 

  /* Initialise MatInv */
  Vector_Set(MatInv->p[0],0,k*k);

  /* Initialize 'MatInv' to Identity matrix form. Each diagonal entry is set*/
  /* to 1. Last column of each row (denominator of each entry in a row) is  */
  /* also set to 1.                                                         */ 
  for(i=0;i<k;++i) {
    value_set_si(MatInv->p[i][i],1);	
    /* value_set_si(MatInv->p[i][k],1);	/* denum */
  }  
  /* Apply Gauss-Jordan elimination method on the two matrices 'Mat' and  */
  /* 'MatInv' in parallel.                                                */
  for(i=0;i<k;++i) {
    
    /* Check if the diagonal entry (new pivot) is non-zero or not */
    if(value_zero_p(Mat->p[i][i])) {   	
      
      /* Search for a non-zero pivot down the column(i) */
      for(j=i;j<k;++j)      
	if(value_notzero_p(Mat->p[j][i]))
	  break;
      
      /* If no non-zero pivot is found, the matrix 'Mat' is non-invertible */
      /* Return 0.                                                         */
      if(j==k) {
	
	/* Clear all the 'Value' variables */
	value_clear(x);  value_clear(gcd); value_clear(piv);
	value_clear(m1); value_clear(m2);
	return 0;
      }	
      
      /* Exchange the rows, row(i) and row(j) so that the diagonal element */
      /* Mat->p[i][i] (pivot) is non-zero. Repeat the same operations on    */
      /* matrix 'MatInv'.                                                   */
      for(c=0;c<k;++c) {

	/* Interchange rows, row(i) and row(j) of matrix 'Mat'    */
	value_assign(x,Mat->p[j][c]);
	value_assign(Mat->p[j][c],Mat->p[i][c]);
	value_assign(Mat->p[i][c],x);
	
	/* Interchange rows, row(i) and row(j) of matrix 'MatInv' */
	value_assign(x,MatInv->p[j][c]);
	value_assign(MatInv->p[j][c],MatInv->p[i][c]);
	value_assign(MatInv->p[i][c],x);
      }
    }
    
    /* Make all the entries in column(i) of matrix 'Mat' zero except the */
    /* diagonal entry. Repeat the same sequence of operations on matrix  */
    /* 'MatInv'.                                                         */
    for(j=0;j<k;++j) {
      if (j==i) continue;	         /* Skip the pivot */
      value_assign(x,Mat->p[j][i]);
      if(value_notzero_p(x)) {
	value_assign(piv,Mat->p[i][i]);
	value_gcd(gcd, x, piv);
	if (value_notone_p(gcd) ) {
	  value_divexact(x, x, gcd);
	  value_divexact(piv, piv, gcd);
	}
	for(c=((j>i)?i:0);c<k;++c) {
	  value_multiply(m1,piv,Mat->p[j][c]);
	  value_multiply(m2,x,Mat->p[i][c]);
	  value_subtract(Mat->p[j][c],m1,m2); 
	}
	for(c=0;c<k;++c) {
	  value_multiply(m1,piv,MatInv->p[j][c]);
	  value_multiply(m2,x,MatInv->p[i][c]);
	  value_subtract(MatInv->p[j][c],m1,m2);
	}
	      
	/* Simplify row(j) of the two matrices 'Mat' and 'MatInv' by */
	/* dividing the rows with the common GCD.                     */
	Vector_Gcd(&MatInv->p[j][0],k,&m1);
	Vector_Gcd(&Mat->p[j][0],k,&m2);
	value_gcd(gcd, m1, m2);
	if(value_notone_p(gcd)) {
	  for(c=0;c<k;++c) {
	    value_divexact(Mat->p[j][c], Mat->p[j][c], gcd);
	    value_divexact(MatInv->p[j][c], MatInv->p[j][c], gcd);
	  }
	}
      }
    }
  }
  
  /* Find common denom for each row */ 
   den = (Value *)malloc(k*sizeof(Value));
   value_set_si(x,1);
   for(j=0 ; j<k ; ++j) {
     value_init(den[j]);
     value_assign(den[j],Mat->p[j][j]);
     
     /* gcd is always positive */
     Vector_Gcd(&MatInv->p[j][0],k,&gcd);
     value_gcd(gcd, gcd, den[j]);
     if (value_neg_p(den[j])) 
       value_oppose(gcd,gcd); /* make denominator positive */
     if (value_notone_p(gcd)) {
       for (c=0; c<k; c++) 
	 value_divexact(MatInv->p[j][c], MatInv->p[j][c], gcd); /* normalize */
       value_divexact(den[j], den[j], gcd);
     }  
     value_gcd(gcd, x, den[j]);
     value_divexact(m1, den[j], gcd);
     value_multiply(x,x,m1);
   }
   if (value_notone_p(x)) 
     for(j=0 ; j<k ; ++j) {       
       for (c=0; c<k; c++) {
	 value_division(m1,x,den[j]);
	 value_multiply(MatInv->p[j][c],MatInv->p[j][c],m1);  /* normalize */
       }
     }

   /* Clear all the 'Value' variables */
   for(j=0 ; j<k ; ++j) {
     value_clear(den[j]);
   }  
   value_clear(x);  value_clear(gcd); value_clear(piv);
   value_clear(m1); value_clear(m2);
   free(den);
   
   return 1;
} /* Matrix_Inverse */
Пример #11
0
/* 
 * Basic hermite engine 
 */
static int hermite(Matrix *H,Matrix *U,Matrix *Q) {
  
  int nc, nr, i, j, k, rank, reduced, pivotrow;
  Value pivot,x,aux;
  Value *temp1, *temp2;
  
  /*                     T                     -1   T */
  /* Computes form: A = Q H  and U A = H  and U  = Q  */
  
  if (!H) { 
    errormsg1("Domlib", "nullH", "hermite: ? Null H");
    return -1;
  }
  nc = H->NbColumns;
  nr = H->NbRows;
  temp1 = (Value *) malloc(nc * sizeof(Value));
  temp2 = (Value *) malloc(nr * sizeof(Value));
  if (!temp1 ||!temp2) {
    errormsg1("Domlib", "outofmem", "out of memory space");
    return -1;
  }
  
  /* Initialize all the 'Value' variables */
  value_init(pivot); value_init(x); 
  value_init(aux);   
  for(i=0;i<nc;i++)
    value_init(temp1[i]);
  for(i=0;i<nr;i++)
    value_init(temp2[i]);
  
#ifdef DEBUG
  fprintf(stderr,"Start  -----------\n");
  Matrix_Print(stderr,0,H);
#endif
  for (k=0, rank=0; k<nc && rank<nr; k=k+1) {
    reduced = 1;	/* go through loop the first time */
#ifdef DEBUG
    fprintf(stderr, "Working on col %d.  Rank=%d ----------\n", k+1, rank+1);
#endif
    while (reduced) {
      reduced=0;
      
      /* 1. find pivot row */
      value_absolute(pivot,H->p[rank][k]);
      
      /* the kth-diagonal element */
      pivotrow = rank;
      
      /* find the row i>rank with smallest nonzero element in col k */
      for (i=rank+1; i<nr; i++) {
	value_absolute(x,H->p[i][k]);
	if (value_notzero_p(x) &&
	    (value_lt(x,pivot) || value_zero_p(pivot))) {
	  value_assign(pivot,x);
	  pivotrow = i;
	}
      }
      
      /* 2. Bring pivot to diagonal (exchange rows pivotrow and rank) */
      if (pivotrow != rank) {
	Vector_Exchange(H->p[pivotrow],H->p[rank],nc);
	if (U)
	  Vector_Exchange(U->p[pivotrow],U->p[rank],nr);
	if (Q)
	  Vector_Exchange(Q->p[pivotrow],Q->p[rank],nr);

#ifdef DEBUG
	fprintf(stderr,"Exchange rows %d and %d  -----------\n", rank+1, pivotrow+1);
	Matrix_Print(stderr,0,H);
#endif
      }
      value_assign(pivot,H->p[rank][k]);	/* actual ( no abs() ) pivot */
      
      /* 3. Invert the row 'rank' if pivot is negative */
      if (value_neg_p(pivot)) {
	value_oppose(pivot,pivot); /* pivot = -pivot */
	for (j=0; j<nc; j++)
	  value_oppose(H->p[rank][j],H->p[rank][j]);
	
	/* H->p[rank][j] = -(H->p[rank][j]); */
	if (U)
	  for (j=0; j<nr; j++)
	    value_oppose(U->p[rank][j],U->p[rank][j]);
	
	/* U->p[rank][j] = -(U->p[rank][j]); */
	if (Q)
	  for (j=0; j<nr; j++)
	    value_oppose(Q->p[rank][j],Q->p[rank][j]);
	
	/* Q->p[rank][j] = -(Q->p[rank][j]); */
#ifdef DEBUG
	fprintf(stderr,"Negate row %d  -----------\n", rank+1);
	Matrix_Print(stderr,0,H);
#endif

      }      
      if (value_notzero_p(pivot)) {
	
	/* 4. Reduce the column modulo the pivot */
	/*    This eventually zeros out everything below the */
	/*    diagonal and produces an upper triangular matrix */
	
	for (i=rank+1;i<nr;i++) {
	  value_assign(x,H->p[i][k]);
	  if (value_notzero_p(x)) {	    
	    value_modulus(aux,x,pivot);
	    
	    /* floor[integer division] (corrected for neg x) */
	    if (value_neg_p(x) && value_notzero_p(aux)) {
	      
	      /* x=(x/pivot)-1; */
	      value_division(x,x,pivot);
	      value_decrement(x,x);
	    }	
	    else 
	      value_division(x,x,pivot);
	    for (j=0; j<nc; j++) {
	      value_multiply(aux,x,H->p[rank][j]);
	      value_subtract(H->p[i][j],H->p[i][j],aux);
	    }
	    
	    /* U->p[i][j] -= (x * U->p[rank][j]); */
	    if (U)
	      for (j=0; j<nr; j++) {
		value_multiply(aux,x,U->p[rank][j]);
		value_subtract(U->p[i][j],U->p[i][j],aux);
	      }
	    
	    /* Q->p[rank][j] += (x * Q->p[i][j]); */
	    if (Q)
	      for(j=0;j<nr;j++) {
		value_addmul(Q->p[rank][j], x, Q->p[i][j]);
	      }
	    reduced = 1;

#ifdef DEBUG
	    fprintf(stderr,
		    "row %d = row %d - %d row %d -----------\n", i+1, i+1, x, rank+1);
	    Matrix_Print(stderr,0,H);
#endif
	
	  } /* if (x) */
	} /* for (i) */
      } /* if (pivot != 0) */
    } /* while (reduced) */
    
    /* Last finish up this column */
    /* 5. Make pivot column positive (above pivot row) */
    /*    x should be zero for i>k */
    
    if (value_notzero_p(pivot)) {
      for (i=0; i<rank; i++) {
	value_assign(x,H->p[i][k]);
	if (value_notzero_p(x)) { 	  
	  value_modulus(aux,x,pivot);
	  
	  /* floor[integer division] (corrected for neg x) */
	  if (value_neg_p(x) && value_notzero_p(aux)) {
	    value_division(x,x,pivot);
	    value_decrement(x,x);
	    
	    /* x=(x/pivot)-1; */
	  }
	  else
	    value_division(x,x,pivot);
	  
	  /* H->p[i][j] -= x * H->p[rank][j]; */
	  for (j=0; j<nc; j++) {
	    value_multiply(aux,x,H->p[rank][j]);
	    value_subtract(H->p[i][j],H->p[i][j],aux);
	  }
	  
	  /* U->p[i][j] -= x * U->p[rank][j]; */
	  if (U)
	    for (j=0; j<nr; j++) {
	      value_multiply(aux,x,U->p[rank][j]);
	      value_subtract(U->p[i][j],U->p[i][j],aux);
	    }
	  
	  /* Q->p[rank][j] += x * Q->p[i][j]; */
	  if (Q)
	    for (j=0; j<nr; j++) {
	      value_addmul(Q->p[rank][j], x, Q->p[i][j]);
	    }  
#ifdef DEBUG
	  fprintf(stderr,
		  "row %d = row %d - %d row %d -----------\n", i+1, i+1, x, rank+1);
	  Matrix_Print(stderr,0,H);
#endif
	} /* if (x) */
      } /* for (i) */
      rank++;
    } /* if (pivot!=0) */
  } /* for (k) */
  
  /* Clear all the 'Value' variables */
  value_clear(pivot); value_clear(x); 
  value_clear(aux); 
  for(i=0;i<nc;i++)
    value_clear(temp1[i]);
  for(i=0;i<nr;i++)
    value_clear(temp2[i]);
  free(temp2);
  free(temp1);
  return rank;
} /* Hermite */ 
Пример #12
0
/**
 * Tests Constraints_fullDimensionize by comparing the Ehrhart polynomials 
 * @param A the input set of constraints
 * @param B the corresponding context
 * @param the number of samples to generate for the test
 * @return 1 if the Ehrhart polynomial had the same value for the
 * full-dimensional and non-full-dimensional sets of constraints, for their
 * corresponding sample parameters values.
 */
int test_Constraints_fullDimensionize(Matrix * A, Matrix * B, 
				      unsigned int nbSamples) {
  Matrix * Eqs= NULL, *ParmEqs=NULL, *VL=NULL;
  unsigned int * elimVars=NULL, * elimParms=NULL;
  Matrix * sample, * smallerSample=NULL;
  Matrix * transfSample=NULL;
  Matrix * parmVL=NULL;
  unsigned int i, j, r, nbOrigParms, nbParms;
  Value div, mod, *origVal=NULL, *fullVal=NULL;
  Matrix * VLInv;
  Polyhedron * P, *PC;
  Matrix * M, *C;
  Enumeration * origEP, * fullEP=NULL;
  const char **fullNames = NULL;
  int isOk = 1; /* holds the result */

  /* compute the origial Ehrhart polynomial */
  M = Matrix_Copy(A);
  C = Matrix_Copy(B);
  P = Constraints2Polyhedron(M, maxRays);
  PC = Constraints2Polyhedron(C, maxRays);
  origEP = Polyhedron_Enumerate(P, PC, maxRays, origNames);
  Matrix_Free(M);
  Matrix_Free(C);
  Polyhedron_Free(P);
  Polyhedron_Free(PC);

  /* compute the full-dimensional polyhedron corresponding to A and its Ehrhart
     polynomial */
  M = Matrix_Copy(A);
  C = Matrix_Copy(B);
  nbOrigParms = B->NbColumns-2;
  Constraints_fullDimensionize(&M, &C, &VL, &Eqs, &ParmEqs, 
			       &elimVars, &elimParms, maxRays);
  if ((Eqs->NbRows==0) && (ParmEqs->NbRows==0)) {
    Matrix_Free(M);
    Matrix_Free(C);
    Matrix_Free(Eqs);
    Matrix_Free(ParmEqs);
    free(elimVars);
    free(elimParms);
    return 1;
  }
  nbParms = C->NbColumns-2;
  P = Constraints2Polyhedron(M, maxRays);
  PC = Constraints2Polyhedron(C, maxRays);
  namesWithoutElim(origNames, nbOrigParms, elimParms, &fullNames);
  fullEP = Polyhedron_Enumerate(P, PC, maxRays, fullNames);
  Matrix_Free(M);
  Matrix_Free(C);
  Polyhedron_Free(P);
  Polyhedron_Free(PC);
  
  /* make a set of sample parameter values and compare the corresponding
     Ehrhart polnomials */
  sample = Matrix_Alloc(1,nbOrigParms);
  transfSample = Matrix_Alloc(1, nbParms);
  Lattice_extractSubLattice(VL, nbParms, &parmVL);
  VLInv = Matrix_Alloc(parmVL->NbRows, parmVL->NbRows+1);
  MatInverse(parmVL, VLInv);
  if (dbg) {
    show_matrix(parmVL);
    show_matrix(VLInv);
  }
  srand(nbSamples);
  value_init(mod);
  value_init(div);
  for (i = 0; i< nbSamples; i++) {
    /* create a random sample */
    for (j=0; j< nbOrigParms; j++) {
      value_set_si(sample->p[0][j], rand()%100);
    }
    /* compute the corresponding value for the full-dimensional
       constraints */
    valuesWithoutElim(sample, elimParms, &smallerSample); 
    /* (N' i' 1)^T = VLinv.(N i 1)^T*/
    for (r = 0; r < nbParms; r++) {
      Inner_Product(&(VLInv->p[r][0]), smallerSample->p[0], nbParms,
		    &(transfSample->p[0][r]));
      /* add the constant part */
      value_addto(transfSample->p[0][r], transfSample->p[0][r], 
					 VLInv->p[r][VLInv->NbColumns-2]);
      value_pdivision(div, transfSample->p[0][r], 
			 VLInv->p[r][VLInv->NbColumns-1]);
      value_subtract(mod, transfSample->p[0][r], div);
      /* if the parameters value does not belong to the validity lattice, the
	 Ehrhart polynomial is zero. */
      if (!value_zero_p(mod)) {
	fullEP = Enumeration_zero(nbParms, maxRays);
	break;
      }
    }
    /* compare the two forms of the Ehrhart polynomial.*/
    if (origEP ==NULL) break; /* NULL has loose semantics for EPs */
    origVal = compute_poly(origEP, sample->p[0]);
    fullVal = compute_poly(fullEP, transfSample->p[0]);
    if (!value_eq(*origVal, *fullVal)) {
      isOk = 0;
      printf("EPs don't match. \n Original value = ");
      value_print(stdout, VALUE_FMT, *origVal);
      printf("\n Original sample = [");
      for (j=0; j<sample->NbColumns; j++) {
	value_print(stdout, VALUE_FMT, sample->p[0][j]);
	printf(" ");
      }
      printf("] \n EP = ");
      if(origEP!=NULL) {
	print_evalue(stdout, &(origEP->EP), origNames);
      }
      else {
	printf("NULL");
      }
      printf(" \n Full-dimensional value = ");
      value_print(stdout, P_VALUE_FMT, *fullVal);
      printf("\n full-dimensional sample = [");
      for (j=0; j<sample->NbColumns; j++) {
	value_print(stdout, VALUE_FMT, transfSample->p[0][j]);
	printf(" ");
      }
      printf("] \n EP = ");
      if(origEP!=NULL) {
	print_evalue(stdout, &(origEP->EP), fullNames);
      }
      else {
	printf("NULL");
      }
    }
    if (dbg) {
      printf("\nOriginal value = ");
      value_print(stdout, VALUE_FMT, *origVal);
      printf("\nFull-dimensional value = ");
      value_print(stdout, P_VALUE_FMT, *fullVal);
      printf("\n");
    }
    value_clear(*origVal);
    value_clear(*fullVal);
  }
  value_clear(mod);
  value_clear(div);
  Matrix_Free(sample);
  Matrix_Free(smallerSample);
  Matrix_Free(transfSample);
  Enumeration_Free(origEP);
  Enumeration_Free(fullEP);
  return isOk;
} /* test_Constraints_fullDimensionize */
Пример #13
0
/* GaussSimplify --
   Given Mat1, a matrix of equalities, performs Gaussian elimination.
   Find a minimum basis, Returns the rank.
   Mat1 is context, Mat2 is reduced in context of Mat1
*/
int GaussSimplify(Matrix *Mat1,Matrix *Mat2) {
  
  int NbRows = Mat1->NbRows;
  int NbCols = Mat1->NbColumns;
  int *column_index;
  int i, j, k, n, t, pivot, Rank; 
  Value gcd, tmp, *cp; 
  
  column_index=(int *)malloc(NbCols * sizeof(int));
  if (!column_index) {
    errormsg1("GaussSimplify", "outofmem", "out of memory space\n");
    Pol_status = 1;
    return 0;
  }
  
  /* Initialize all the 'Value' variables */
  value_init(gcd); value_init(tmp);
  
  Rank=0;
  for (j=0; j<NbCols; j++) {		  /* for each column starting at */ 
    for (i=Rank; i<NbRows; i++)		  /* diagonal, look down to find */
      if (value_notzero_p(Mat1->p[i][j])) /* the first non-zero entry    */
	break;	                         
    if (i!=NbRows) {			  /* was one found ? */
      if (i!=Rank)			  /* was it found below the diagonal?*/
	Vector_Exchange(Mat1->p[Rank],Mat1->p[i],NbCols);
      
      /* Normalize the pivot row */
      Vector_Gcd(Mat1->p[Rank],NbCols,&gcd);
      
      /* If (gcd >= 2) */
      value_set_si(tmp,2);
      if (value_ge(gcd,tmp)) {
	cp = Mat1->p[Rank];
        for (k=0; k<NbCols; k++,cp++)
          value_division(*cp,*cp,gcd);		
      }
      if (value_neg_p(Mat1->p[Rank][j])) {
	cp = Mat1->p[Rank];
	for (k=0; k<NbCols; k++,cp++)
	  value_oppose(*cp,*cp);
      }
      /* End of normalize */
      pivot=i;
      for (i=0;i<NbRows;i++)	/* Zero out the rest of the column */
	if (i!=Rank) {
	  if (value_notzero_p(Mat1->p[i][j])) {
	    Value a, a1, a2, a1abs, a2abs;
	    value_init(a); value_init(a1); value_init(a2);
            value_init(a1abs); value_init(a2abs);
            value_assign(a1,Mat1->p[i][j]);
            value_absolute(a1abs,a1);
            value_assign(a2,Mat1->p[Rank][j]); 
            value_absolute(a2abs,a2);
            value_gcd(a, a1abs, a2abs);
	    value_divexact(a1, a1, a);
	    value_divexact(a2, a2, a);
	    value_oppose(a1,a1);
	    Vector_Combine(Mat1->p[i],Mat1->p[Rank],Mat1->p[i],a2, 
			   a1,NbCols);
	    Vector_Normalize(Mat1->p[i],NbCols);
	    value_clear(a); value_clear(a1); value_clear(a2);
            value_clear(a1abs); value_clear(a2abs);
          }
	}
      column_index[Rank]=j;
      Rank++;
    }
  } /* end of Gauss elimination */


  if (Mat2) {  /* Mat2 is a transformation matrix  (i,j->f(i,j))....
		  can't scale it because can't scale both sides of -> */
    /* normalizes an affine transformation        */
    /* priority of forms                          */
    /*    1. i' -> i                (identity)    */
    /*    2. i' -> i + constant     (uniform)     */
    /*    3. i' -> constant         (broadcast)   */
    /*    4. i' -> j                (permutation) */
    /*    5. i' -> j + constant     (      )      */
    /*    6. i' -> i + j + constant (non-uniform) */
    for (k=0; k<Rank; k++) {
      j = column_index[k];
      for (i=0; i<(Mat2->NbRows-1);i++) {   /* all but the last row 0...0 1 */
	if ((i!=j) && value_notzero_p(Mat2->p[i][j])) {
	  
	  /* Remove dependency of i' on j */
          Value a, a1, a1abs, a2, a2abs;
	  value_init(a); value_init(a1); value_init(a2);
          value_init(a1abs); value_init(a2abs);
	  value_assign(a1,Mat2->p[i][j]);
	  value_absolute(a1abs,a1);
	  value_assign(a2,Mat1->p[k][j]);
	  value_absolute(a2abs,a2);
	  value_gcd(a, a1abs, a2abs);
	  value_divexact(a1, a1, a);
	  value_divexact(a2, a2, a);
	  value_oppose(a1,a1);
	  if (value_one_p(a2)) {
            Vector_Combine(Mat2->p[i],Mat1->p[k],Mat2->p[i],a2,
			   a1,NbCols);
	    
	    /* Vector_Normalize(Mat2->p[i],NbCols); -- can't do T        */
	  } /* otherwise, can't do it without mult lhs prod (2i,3j->...) */
	  value_clear(a); value_clear(a1); value_clear(a2);
          value_clear(a1abs); value_clear(a2abs);
                
	}
        else if ((i==j) && value_zero_p(Mat2->p[i][j])) {
	  
	  /* 'i' does not depend on j */
	  for (n=j+1; n < (NbCols-1); n++) {
	    if (value_notzero_p(Mat2->p[i][n])) { /* i' depends on some n */
	      value_set_si(tmp,1);
              Vector_Combine(Mat2->p[i],Mat1->p[k],Mat2->p[i],tmp,
			     tmp,NbCols);
	      break;
	    }  /* if 'i' depends on just a constant, then leave it alone.*/
	  }
        }
      }
    }
    
    /* Check last row of transformation Mat2 */
    for (j=0; j<(NbCols-1); j++)
      if (value_notzero_p(Mat2->p[Mat2->NbRows-1][j])) {
	errormsg1("GaussSimplify", "corrtrans", "Corrupted transformation\n");
	break;
      }
    
    if (value_notone_p(Mat2->p[Mat2->NbRows-1][NbCols-1])) {
      errormsg1("GaussSimplify", "corrtrans", "Corrupted transformation\n");
    }
  }
  value_clear(gcd); value_clear(tmp);
  free(column_index);
  return Rank;
} /* GaussSimplify */
Пример #14
0
/* INDEX  = 1 .... Dimension      */
int PolyhedronLTQ (Polyhedron *Pol1,Polyhedron *Pol2,int INDEX, int PDIM, int NbMaxConstrs) { 
  
  int res, dim, i, j, k;
  Polyhedron *Q1, *Q2, *Q3, *Q4, *Q;
  Matrix *Mat;

  if (Pol1->next || Pol2->next) {
    errormsg1("PolyhedronLTQ", "compoly", "Can only compare polyhedra");
    return 0;
  }
  if (Pol1->Dimension != Pol2->Dimension) {
    errormsg1("PolyhedronLTQ","diffdim","Polyhedra are not same dimension");
    return 0;
  }
  dim = Pol1->Dimension+2;

  POL_ENSURE_FACETS(Pol1);
  POL_ENSURE_VERTICES(Pol1);
  POL_ENSURE_FACETS(Pol2);
  POL_ENSURE_VERTICES(Pol2);
  
#ifdef DEBUG
  fprintf(stdout, "P1\n");
  Polyhedron_Print(stdout,P_VALUE_FMT,Pol1);
  fprintf(stdout, "P2\n");
  Polyhedron_Print(stdout,P_VALUE_FMT,Pol2);
#endif
  
  /* Create the Line to add */
  k = Pol1->Dimension-INDEX+1-PDIM;
  Mat = Matrix_Alloc(k,dim);
  Vector_Set(Mat->p_Init,0,dim*k);
  for(j=0,i=INDEX;j<k;i++,j++)
    value_set_si(Mat->p[j][i],1);
  
  Q1 = AddRays(Mat->p[0],k,Pol1,NbMaxConstrs);
  Q2 = AddRays(Mat->p[0],k,Pol2,NbMaxConstrs);

#ifdef DEBUG
  fprintf(stdout, "Q1\n");
  Polyhedron_Print(stdout,P_VALUE_FMT,Q1);
  fprintf(stdout, "Q2\n");
  Polyhedron_Print(stdout,P_VALUE_FMT,Q2);
#endif
  
  Matrix_Free(Mat);
  Q  = DomainIntersection(Q1,Q2,NbMaxConstrs);
  
#ifdef DEBUG
  fprintf(stdout, "Q\n");
  Polyhedron_Print(stdout,P_VALUE_FMT,Q);
#endif
  
  Domain_Free(Q1);
  Domain_Free(Q2);
  
  if (emptyQ(Q)) res = 0;	/* not comparable */
  else {
    Q1 = DomainIntersection(Pol1,Q,NbMaxConstrs);
    Q2 = DomainIntersection(Pol2,Q,NbMaxConstrs);
    
#ifdef DEBUG
    fprintf(stdout, "Q1\n");
    Polyhedron_Print(stdout,P_VALUE_FMT,Q1);
    fprintf(stdout, "Q2\n");
    Polyhedron_Print(stdout,P_VALUE_FMT,Q2);
#endif

    k = Q1->NbConstraints + Q2->NbConstraints;
    Mat = Matrix_Alloc(k, dim);
    Vector_Set(Mat->p_Init,0,k*dim);
    
    /* First compute surrounding polyhedron */    
    j=0;
    for (i=0; i<Q1->NbConstraints; i++) {
      if ((value_one_p(Q1->Constraint[i][0])) && (value_pos_p(Q1->Constraint[i][INDEX]))) {
	
	/* keep Q1's lower bounds */
	for (k=0; k<dim; k++) 
	  value_assign(Mat->p[j][k],Q1->Constraint[i][k]);
	j++;
      }
    }
    for (i=0; i<Q2->NbConstraints; i++) {
      if ((value_one_p(Q2->Constraint[i][0])) && (value_neg_p(Q2->Constraint[i][INDEX]))) {
	
	/* and keep Q2's upper bounds */
	for (k=0; k<dim; k++) 
	  value_assign(Mat->p[j][k],Q2->Constraint[i][k]);
	j++;
      }
    }
    Q4 = AddConstraints(Mat->p[0], j, Q, NbMaxConstrs);
    Matrix_Free(Mat);
    
#ifdef debug
    fprintf(stderr, "Q4 surrounding polyhedron\n");
    Polyhderon_Print(stderr,P_VALUE_FMT, Q4);
#endif

    /* if surrounding polyhedron is empty, D1>D2 */
    if (emptyQ(Q4)) {
      res = 1;
      
#ifdef debug
      fprintf(stderr, "Surrounding polyhedron is empty\n");
#endif
      goto LTQdone2; 
    }
    
    /* Test if Q1 < Q2 */      
    /* Build a constraint array for >= Q1 and <= Q2 */
    Mat = Matrix_Alloc(2,dim);
    Vector_Set(Mat->p_Init,0,2*dim);
    
    /* Choose a contraint from Q1 */
    for (i=0; i<Q1->NbConstraints; i++) {
      if (value_zero_p(Q1->Constraint[i][0])) {
	
	/* Equality */
	if (value_zero_p(Q1->Constraint[i][INDEX])) {
	  
	  /* Ignore side constraint (they are in Q) */
	  continue;
	}
	else if (value_neg_p(Q1->Constraint[i][INDEX])) {
	  
	  /* copy -constraint to Mat */
	  value_set_si(Mat->p[0][0],1);
	  for (k=1; k<dim; k++)
	    value_oppose(Mat->p[0][k],Q1->Constraint[i][k]);
	}
	else {
	  
	  /* Copy constraint to Mat */
	  
	  value_set_si(Mat->p[0][0],1);
	  for (k=1; k<dim; k++)
	    value_assign(Mat->p[0][k],Q1->Constraint[i][k]);
	}
      }
      else if(value_neg_p(Q1->Constraint[i][INDEX])) {
	
	/* Upper bound -- make a lower bound from it */
	value_set_si(Mat->p[0][0],1);
	for (k=1; k<dim; k++)
	  value_oppose(Mat->p[0][k],Q1->Constraint[i][k]);
      }
      else {	
	
	/* Lower or side bound -- ignore it */
	continue;
      }
      
      /* Choose a constraint from Q2 */
      for (j=0; j<Q2->NbConstraints; j++) {
	if (value_zero_p(Q2->Constraint[j][0])) {   /* equality */
	  if (value_zero_p(Q2->Constraint[j][INDEX])) {
	    
	    /* Ignore side constraint (they are in Q) */
	    continue;
	  }
	  else if (value_pos_p(Q2->Constraint[j][INDEX])) {
	    
	    /* Copy -constraint to Mat */
	    value_set_si(Mat->p[1][0],1);
	    for (k=1; k<dim; k++)
	      value_oppose(Mat->p[1][k],Q2->Constraint[j][k]);
	  }
	  else {
	    
	    /* Copy constraint to Mat */
	    value_set_si(Mat->p[1][0],1);
	    for (k=1; k<dim; k++)
	      value_assign(Mat->p[1][k],Q2->Constraint[j][k]);
	  };
	}
	else if (value_pos_p(Q2->Constraint[j][INDEX])) {
	  
	  /* Lower bound -- make an upper bound from it */
	  value_set_si(Mat->p[1][0],1);
	  for(k=1;k<dim;k++)
	    value_oppose(Mat->p[1][k],Q2->Constraint[j][k]);
	}
	else {
	  
	  /* Upper or side bound -- ignore it */
	  continue;
	};
	
#ifdef DEBUG
	fprintf(stdout, "i=%d j=%d M=\n", i+1, j+1);
	Matrix_Print(stdout,P_VALUE_FMT,Mat);
#endif
	
	/* Add Mat to Q and see if anything is made */
	Q3 = AddConstraints(Mat->p[0],2,Q,NbMaxConstrs);

#ifdef DEBUG
	fprintf(stdout, "Q3\n");
	Polyhedron_Print(stdout,P_VALUE_FMT,Q3);
#endif
	
	if (!emptyQ(Q3)) { 
	  Domain_Free(Q3);
	  
#ifdef DEBUG
	  fprintf(stdout, "not empty\n");
#endif
	  res = -1;
	  goto LTQdone;
	}
#ifdef DEBUG
	fprintf(stdout,"empty\n");	
#endif
	Domain_Free(Q3);
      } /* end for j */
    } /* end for i */
    res = 1;
LTQdone:
    Matrix_Free(Mat);
LTQdone2: 
    Domain_Free(Q4);
    Domain_Free(Q1);
    Domain_Free(Q2);
  }
  Domain_Free(Q);
  
#ifdef DEBUG
  fprintf(stdout, "res = %d\n", res);
#endif
  
  return res;
} /* PolyhedronLTQ */