void ddf_InitialDataSetup(ddf_ConePtr cone)
{
long j, r;
ddf_rowset ZSet;
static ddf_Arow Vector1,Vector2;
static ddf_colrange last_d=0;
if (last_d < cone->d){
if (last_d>0) {
for (j=0; j<last_d; j++){
ddf_clear(Vector1[j]);
ddf_clear(Vector2[j]);
}
free(Vector1); free(Vector2);
}
Vector1=(myfloat*)calloc(cone->d,sizeof(myfloat));
Vector2=(myfloat*)calloc(cone->d,sizeof(myfloat));
for (j=0; j<cone->d; j++){
ddf_init(Vector1[j]);
ddf_init(Vector2[j]);
}
last_d=cone->d;
}
cone->RecomputeRowOrder=ddf_FALSE;
cone->ArtificialRay = NULL;
cone->FirstRay = NULL;
cone->LastRay = NULL;
set_initialize(&ZSet,cone->m);
ddf_AddArtificialRay(cone);
set_copy(cone->AddedHalfspaces, cone->InitialHalfspaces);
set_copy(cone->WeaklyAddedHalfspaces, cone->InitialHalfspaces);
ddf_UpdateRowOrderVector(cone, cone->InitialHalfspaces);
for (r = 1; r <= cone->d; r++) {
for (j = 0; j < cone->d; j++){
ddf_set(Vector1[j], cone->B[j][r-1]);
ddf_neg(Vector2[j], cone->B[j][r-1]);
}
ddf_Normalize(cone->d, Vector1);
ddf_Normalize(cone->d, Vector2);
ddf_ZeroIndexSet(cone->m, cone->d, cone->A, Vector1, ZSet);
if (set_subset(cone->EqualitySet, ZSet)){
if (ddf_debug) {
fprintf(stderr,"add an initial ray with zero set:");
set_fwrite(stderr,ZSet);
}
ddf_AddRay(cone, Vector1);
if (cone->InitialRayIndex[r]==0) {
ddf_AddRay(cone, Vector2);
if (ddf_debug) {
fprintf(stderr,"and add its negative also.\n");
}
}
}
}
ddf_CreateInitialEdges(cone);
cone->Iteration = cone->d + 1;
if (cone->Iteration > cone->m) cone->CompStatus=ddf_AllFound; /* 0.94b */
set_free(ZSet);
ddf_MatrixPtr ddf_FourierElimination(ddf_MatrixPtr M,ddf_ErrorType *error)
/* Eliminate the last variable (column) from the given H-matrix using
the standard Fourier Elimination.
*/
{
ddf_MatrixPtr Mnew=NULL;
ddf_rowrange i,inew,ip,in,iz,m,mpos=0,mneg=0,mzero=0,mnew;
ddf_colrange j,d,dnew;
ddf_rowindex posrowindex, negrowindex,zerorowindex;
myfloat temp1,temp2;
ddf_boolean localdebug=ddf_FALSE;
*error=ddf_NoError;
m= M->rowsize;
d= M->colsize;
if (d<=1){
*error=ddf_ColIndexOutOfRange;
if (localdebug) {
printf("The number of column is too small: %ld for Fourier's Elimination.\n",d);
}
goto _L99;
}
if (M->representation==ddf_Generator){
*error=ddf_NotAvailForV;
if (localdebug) {
printf("Fourier's Elimination cannot be applied to a V-polyhedron.\n");
}
goto _L99;
}
if (set_card(M->linset)>0){
*error=ddf_CannotHandleLinearity;
if (localdebug) {
printf("The Fourier Elimination function does not handle equality in this version.\n");
}
goto _L99;
}
/* Create temporary spaces to be removed at the end of this function */
posrowindex=(long*)calloc(m+1,sizeof(long));
negrowindex=(long*)calloc(m+1,sizeof(long));
zerorowindex=(long*)calloc(m+1,sizeof(long));
ddf_init(temp1);
ddf_init(temp2);
for (i = 1; i <= m; i++) {
if (ddf_Positive(M->matrix[i-1][d-1])){
mpos++;
posrowindex[mpos]=i;
} else if (ddf_Negative(M->matrix[i-1][d-1])) {
mneg++;
negrowindex[mneg]=i;
} else {
mzero++;
zerorowindex[mzero]=i;
}
} /*of i*/
if (localdebug) {
ddf_WriteMatrix(stdout, M);
printf("No of (+ - 0) rows = (%ld, %ld, %ld)\n", mpos,mneg, mzero);
}
/* The present code generates so many redundant inequalities and thus
is quite useless, except for very small examples
*/
mnew=mzero+mpos*mneg; /* the total number of rows after elimination */
dnew=d-1;
Mnew=ddf_CreateMatrix(mnew, dnew);
ddf_CopyArow(Mnew->rowvec, M->rowvec, dnew);
/* set_copy(Mnew->linset,M->linset); */
Mnew->numbtype=M->numbtype;
Mnew->representation=M->representation;
Mnew->objective=M->objective;
/* Copy the inequalities independent of x_d to the top of the new matrix. */
for (iz = 1; iz <= mzero; iz++){
for (j = 1; j <= dnew; j++) {
ddf_set(Mnew->matrix[iz-1][j-1], M->matrix[zerorowindex[iz]-1][j-1]);
}
}
/* Create the new inequalities by combining x_d positive and negative ones. */
inew=mzero; /* the index of the last x_d zero inequality */
for (ip = 1; ip <= mpos; ip++){
for (in = 1; in <= mneg; in++){
inew++;
ddf_neg(temp1, M->matrix[negrowindex[in]-1][d-1]);
for (j = 1; j <= dnew; j++) {
ddf_LinearComb(temp2,M->matrix[posrowindex[ip]-1][j-1],temp1,\
M->matrix[negrowindex[in]-1][j-1],\
M->matrix[posrowindex[ip]-1][d-1]);
ddf_set(Mnew->matrix[inew-1][j-1],temp2);
}
ddf_Normalize(dnew,Mnew->matrix[inew-1]);
}
}
free(posrowindex);
free(negrowindex);
free(zerorowindex);
ddf_clear(temp1);
ddf_clear(temp2);
_L99:
return Mnew;
}
