/*
--------------------------------------------------------------
mark the nodes 1 or 2 to define a min-cut,
where source in X and sink in Y.
start the search from the source node.
for x in X and y in Y
arc (x,y) is in the min-cut when flow(x,y) == capacity(x,y)
arc (y,x) is in the min-cut when flow(y,x) == 0
on return, mark[*] is filled with 1 or 2,
where the mark[source] = 1 and mark[sink] = 2
created -- 96jun08, cca
--------------------------------------------------------------
*/
void
Network_findMincutFromSource (
Network *network,
Ideq *deq,
int mark[]
) {
Arc *arc ;
Arc **inheads, **outheads ;
FILE *msgFile ;
int msglvl, nnode, source, x, z ;
/*
---------------
check the input
---------------
*/
if ( network == NULL || (nnode = network->nnode) <= 0
|| deq == NULL || mark == NULL ) {
fprintf(stderr,
"\n fatal error in Network_findMincutFromSource(%p,%p,%p)"
"\n bad input\n", network, deq, mark) ;
exit(-1) ;
}
source = 0 ;
inheads = network->inheads ;
outheads = network->outheads ;
msglvl = network->msglvl ;
msgFile = network->msgFile ;
if ( msglvl > 2 ) {
fprintf(msgFile, "\n Network_findMincutFromSource") ;
fflush(msgFile) ;
}
/*
-----------------------------------------------
load all the nodes into Y except for the source
-----------------------------------------------
*/
IVfill(nnode, mark, 2) ;
mark[source] = 1 ;
/*
---------------------------------------------------------
do a breadth first traversal from the source
visit x in X
out edge (x,z), add z to X if flow(x,z) < capacity(x,z)
in edge (z,x), add z to X if flow(z,x) > 0
---------------------------------------------------------
*/
Ideq_clear(deq) ;
Ideq_insertAtHead(deq, source) ;
while ( (x = Ideq_removeFromHead(deq)) != -1 ) {
if ( msglvl > 2 ) {
fprintf(msgFile, "\n checking out node %d", x) ;
fflush(msgFile) ;
}
for ( arc = outheads[x] ; arc != NULL ; arc = arc->nextOut ) {
z = arc->second ;
if ( mark[z] != 1 ) {
if ( msglvl > 2 ) {
fprintf(msgFile,
"\n out-arc (%d,%d), flow %d, capacity %d",
x, z, arc->flow, arc->capacity) ;
fflush(msgFile) ;
}
if ( arc->flow < arc->capacity ) {
if ( msglvl > 2 ) {
fprintf(msgFile, ", adding %d to X", z) ;
fflush(msgFile) ;
}
Ideq_insertAtTail(deq, z) ;
mark[z] = 1 ;
}
}
}
for ( arc = inheads[x] ; arc != NULL ; arc = arc->nextIn ) {
z = arc->first ;
if ( mark[z] != 1 ) {
if ( msglvl > 2 ) {
fprintf(msgFile, "\n in-arc (%d,%d), flow %d",
z, x, arc->flow) ;
fflush(msgFile) ;
}
if ( arc->flow > 0 ) {
if ( msglvl > 2 ) {
fprintf(msgFile, ", adding %d to X", z) ;
fflush(msgFile) ;
}
Ideq_insertAtTail(deq, z) ;
mark[z] = 1 ;
}
}
}
}
if ( msglvl > 2 ) {
fprintf(msgFile, "\n leaving FindMincutFromSource") ;
fflush(msgFile) ;
}
return ; }
/*
----------------------------------------------------
purpose -- worker method to factor the matrix
created -- 98may29, cca
----------------------------------------------------
*/
static void *
FrontMtx_QR_workerFactor (
void *arg
) {
char *status ;
ChvList *updlist ;
ChvManager *chvmanager ;
double facops, t0, t1 ;
double *cpus ;
DV workDV ;
FILE *msgFile ;
FrontMtx *frontmtx ;
Ideq *dequeue ;
InpMtx *mtxA ;
int J, K, myid, neqns, nfront, msglvl ;
int *colmap, *firstnz, *nactiveChild, *owners, *par ;
IVL *rowsIVL ;
QR_factorData *data ;
MARKTIME(t0) ;
data = (QR_factorData *) arg ;
mtxA = data->mtxA ;
rowsIVL = data->rowsIVL ;
firstnz = data->firstnz ;
IV_sizeAndEntries(data->ownersIV, &nfront, &owners) ;
frontmtx = data->frontmtx ;
chvmanager = data->chvmanager ;
updlist = data->updlist ;
myid = data->myid ;
cpus = data->cpus ;
msglvl = data->msglvl ;
msgFile = data->msgFile ;
par = frontmtx->tree->par ;
neqns = FrontMtx_neqns(frontmtx) ;
/*
--------------------------------------------------------
status[J] = 'F' --> J finished
= 'W' --> J waiting to be finished
create the Ideq object to handle the bottom-up traversal
nactiveChild[K] = # of unfinished children of K,
when zero, K can be placed on the dequeue
--------------------------------------------------------
*/
status = CVinit(nfront, 'F') ;
dequeue = FrontMtx_setUpDequeue(frontmtx, owners, myid, status,
NULL, 'W', 'F', msglvl, msgFile) ;
FrontMtx_loadActiveLeaves(frontmtx, status, 'W', dequeue) ;
nactiveChild = FrontMtx_nactiveChild(frontmtx, status, myid) ;
colmap = IVinit(neqns, -1) ;
DV_setDefaultFields(&workDV) ;
facops = 0.0 ;
if ( msglvl > 3 ) {
fprintf(msgFile, "\n owners") ;
IVfprintf(msgFile, nfront, owners) ;
fprintf(msgFile, "\n Ideq") ;
Ideq_writeForHumanEye(dequeue, msgFile) ;
fflush(msgFile) ;
}
MARKTIME(t1) ;
cpus[0] += t1 - t0 ;
/*
---------------------------
loop while a path is active
---------------------------
*/
while ( (J = Ideq_removeFromHead(dequeue)) != -1 ) {
if ( msglvl > 1 ) {
fprintf(msgFile, "\n\n ### checking out front %d, owner %d",
J, owners[J]) ;
}
if ( owners[J] == myid ) {
/*
--------------------------------
front J is ready to be processed
--------------------------------
*/
FrontMtx_QR_factorVisit(frontmtx, J, mtxA, rowsIVL, firstnz,
updlist, chvmanager, status, colmap,
&workDV, cpus, &facops, msglvl, msgFile) ;
if ( status[J] == 'F' ) {
/*
------------------------------------------
front J is finished, put parent on dequeue
if it exists or all children are finished
------------------------------------------
*/
if ( (K = par[J]) != -1 && --nactiveChild[K] == 0 ) {
Ideq_insertAtHead(dequeue, K) ;
}
} else {
/*
-----------------------------------------------
front J is not complete, put on tail of dequeue
-----------------------------------------------
*/
Ideq_insertAtTail(dequeue, J) ;
}
} else {
/*
-------------------------------------------
front J is not owned, put parent on dequeue
if it exists and all children are finished
-------------------------------------------
*/
if ( (K = par[J]) != -1 && --nactiveChild[K] == 0 ) {
Ideq_insertAtHead(dequeue, K) ;
}
}
}
data->facops = facops ;
/*
------------------------
free the working storage
------------------------
*/
CVfree(status) ;
Ideq_free(dequeue) ;
IVfree(nactiveChild) ;
IVfree(colmap) ;
DV_clearData(&workDV) ;
MARKTIME(t1) ;
cpus[6] = t1 - t0 ;
cpus[5] = t1 - t0 - cpus[0] - cpus[1]
- cpus[2] - cpus[3] - cpus[4] ;
return(NULL) ;
}
