void load_all(const char* name)
{
bvgraph g = {0};
bvgraph_load(&g, name, strlen(name), 0);
bvgraph_iterator git;
int rval = bvgraph_nonzero_iterator(&g, &git);
if (rval){
printf("Construct nonzero iterator failed. Stop.\n");
return;
}
ALL_PAIR = malloc(sizeof(int)*2*(int)g.m);
for (; bvgraph_iterator_valid(&git); bvgraph_iterator_next(&git)) {
int64_t*links = NULL;
uint64_t d = 0;
bvgraph_iterator_outedges(&git, &links, &d);
int64_t i = 0;
for (i=0; i<d; ++i) {
ALL_PAIR[PAIR_SIZE].from = git.curr;
ALL_PAIR[PAIR_SIZE].to = links[i];
PAIR_SIZE++;
}
}
bvgraph_iterator_free(&git);
}
void iteration(const char* name){
bvgraph g = {0};
bvgraph_load(&g, name, strlen(name), 0);
bvgraph_iterator git;
int rval = bvgraph_nonzero_iterator(&g, &git);
if (rval){
printf("Construct nonzero iterator failed. Stop.\n");
return;
}
for (; bvgraph_iterator_valid(&git); bvgraph_iterator_next(&git)) {
int64_t *links = NULL;
uint64_t d = 0;
bvgraph_iterator_outedges(&git, &links, &d);
printf("node %"PRId64" has degree %"PRId64"\n", git.curr, d);
int64_t i = 0;
for (i=0; i<d; ++i) {
printf("node %"PRId64" links to node %"PRId64"\n", git.curr, links[i]);
}
}
bvgraph_iterator_free(&git);
}
/** Compute a matrix vector product with a substochastic bvgraph structure
*
* y = y + alpha*P'*x where P = D^{-1} A for the adjacency matrix A given
* by a bvgraph structure.
*
* @param g the bvgraph
* @param x the right hand vector,
* @param y the output vector y = y + alpha*P'*x
* @param alpha the value of alpha to adjust the mutliplication by
* @param sum_aPtx the value e^T (alpha*P'*x)
* @return non-zero on error
*/
int mult(omptransbvgraph *tg, double *x, double *y, const double alpha, double *sum_aPtx)
{
bvgraph_parallel_iterators *pits = tg->pits;
int rval=0, j, n=pits->g->n;
double sum0=0, sum1=0, *id=tg->id;
#pragma omp parallel shared(x,y,pits,sum0,sum1,id) \
reduction(|:rval) num_threads(pits->niters)
{
int *links, tid, nsteps; unsigned int i, d; double sumy0, sumy1, t, z;
bvgraph_iterator iter;
tid = omp_get_thread_num();
rval = bvgraph_parallel_iterator(pits, tid, &iter, &nsteps);
sumy0=0.0; sumy1=0.0;
if (rval == 0) {
for (; bvgraph_iterator_valid(&iter) && nsteps;
bvgraph_iterator_next(&iter), nsteps--)
{
double yi=0.0;
bvgraph_iterator_outedges(&iter, &links, &d);
for (i = 0; i < d; i++) {
yi += x[links[i]]*id[links[i]];
}
yi *= alpha;
CSUM2(yi,sumy0,sumy1,t,z);
y[iter.curr]=yi;
}
bvgraph_iterator_free(&iter);
#pragma omp critical
{ CSUM2(FCSUM2(sumy0,sumy1),sum0,sum1,t,z) }
} else {
if (BVGRAPH_VERBOSE) {
fprintf(stderr,"bvgraph_omp_transmult failed on thread %3i\n",
tid);
}
}
}
/**
* Load a graph file but using a set of externally provided buffers
* for the data. This might be useful in the case that you want to managed
* memory for the graph independently of this function.
*
* To maintain the graph, only the bvgraph structure, and the two
* external ararys: gmemory and offsets are required. Consequently,
* a bvgraph structure can always be patched together out of these
* functions.
*
* One common way of using this function would be to first
* load a graph on the disk (bvgraph_load(...,offset_step=-1))
* and then call bvgraph_required_memory with an alternative
* offset step.
*
* @param[in] g a newly created bvgraph structure
* @param[in] filename the base filename for a set of bvgraph files,
* so filename.graph and filename.properties must exist.
* @param[in] offset_step controls how many offsets are loaded,
* if offset_step = -1, then the graph file isn't loaded into memory
* if offset_step = 0, then the graph file is loaded, but no offsets
* no other values are supported at the moment.
* @param[in] gmemory an arry of size gmemsize for the graph
* (if NULL, then this parameter is treated as internal memory)
* @param[in] gmemsize the size of the gmemory block
* @param[in] offsets an array of offsets
* (if NULL, then this parameter is treated as internal memory)
* @param[in] offsetssize the number of offsets
* @return 0 if successful;
* bvgraph_load_error_filename_too_long - indicates the filename was too long
*/
int bvgraph_load_external(bvgraph *g,
const char *filename, unsigned int filenamelen, int offset_step,
unsigned char *gmemory, size_t gmemsize,
unsigned long long* offsets, int offsetssize)
{
int rval = 0;
assert(offset_step == 0 || offset_step == -1 || offset_step == 1);
if (filenamelen > BVGRAPH_MAX_FILENAME_SIZE-1) {
return bvgraph_load_error_filename_too_long;
}
memset(g,0,sizeof(bvgraph));
strncpy(g->filename, filename, filenamelen);
g->filename[filenamelen] = '\0';
g->filenamelen = filenamelen;
g->offset_step = offset_step;
set_defaults(g);
rval = parse_properties(g);
// check for any errors
if (rval != 0) { return rval; }
// continue processing
if (offset_step >= 0)
{
if (offset_step == 0 || offset_step == 1) { //modified 082911
// in this case, we ust load the graph
// file into memory
// first get the filesize
unsigned long long graphfilesize;
char *gfilename = strappend(g->filename, g->filenamelen, ".graph", 6);
rval = fsize(gfilename, &graphfilesize);
free(gfilename);
if (rval) {
return bvgraph_call_io_error;
}
if (gmemory != NULL) {
// they want to use their own memory, make sure
// they allocated enough!
if (gmemsize < graphfilesize) {
return bvgraph_load_error_buffer_too_small;
}
g->memory = gmemory;
g->memory_size = gmemsize;
g->memory_external = 1;
} else {
// we have to allocate the memory ourselves
g->memory_size = (size_t)graphfilesize;
g->memory = malloc(sizeof(unsigned char)*g->memory_size);
if (!g->memory) {
return bvgraph_call_out_of_memory;
}
g->memory_external = 0;
}
// now read the file
gfilename = strappend(g->filename, g->filenamelen, ".graph", 6);
{
size_t bytesread = 0;
FILE *gfile = fopen(gfilename, "rb");
free(gfilename);
if (!gfile) {
return bvgraph_call_io_error;
}
bytesread = fread(g->memory, 1, g->memory_size, gfile);
if (bytesread != graphfilesize) {
return bvgraph_call_io_error;
}
fclose(gfile);
}
// we now have the graph in memory!
if (offset_step == 1) { //modified 082911
// now read the file
char *ofilename = strappend(g->filename, g->filenamelen, ".offsets", 8);
bitfile bf;
long long off = 0;
int64_t i;
FILE *ofile = fopen(ofilename, "rb");
if (offsets != NULL) {
g->offsets = offsets;
g->offsets_external = 1;
} else {
// we have to allocate the memory ourselves
g->offsets = (unsigned long long*) malloc(sizeof(unsigned long long)*g->n);
g->offsets_external = 0;
}
if (ofile) {
rval = bitfile_open(ofile, &bf);
if (rval) {
return bvgraph_call_io_error;
}
for (i = 0; i < g->n; i++){
off = read_offset(g, &bf) + off;
g->offsets[i] = off;
}
} else {
// need to build the offsets
bvgraph_iterator git;
int rval = bvgraph_nonzero_iterator(g, &git);
if (rval) { return rval; }
g->offsets[0] = 0;
for (; bvgraph_iterator_valid(&git); bvgraph_iterator_next(&git)) {
if (git.curr+1 < g->n) {
g->offsets[git.curr+1] = bitfile_tell(&git.bf);
}
}
bvgraph_iterator_free(&git);
}
}
}
}
else
{
g->memory_size = 0;
}
// presently the othercases are not supported, so we don't have to
// worry about them!
return (0);
}
int main(int argc, char **argv)
{
bvgraph graph = {0};
bvgraph *g = &graph;
char *filename;
int filenamelen;
int rval;
int i;
if (argc < 2) { fprintf(stderr, "Usage: bvgraph_test bvgraph_basename\n"); return (-1); }
filename = argv[1];
filenamelen = (int)strlen(filename);
rval = bvgraph_load(g, filename, filenamelen, -1);
if (rval) { perror("error with initial load!"); }
{
size_t memrequired;
bvgraph_required_memory(g, 0, &memrequired, NULL);
printf("the graph %s requires %i bytes to load into memory\n", filename, memrequired);
}
bvgraph_close(g);
rval = bvgraph_load(g, filename, filenamelen, 0);
if (rval) { perror("error with full load!"); }
{
bvgraph_iterator iter;
int *links;
unsigned int d;
// initialize a vector of column sums
int *colsum = malloc(sizeof(int)*g->n);
int *colsum2 = malloc(sizeof(int)*g->n);
int rep;
memset(colsum, 0, sizeof(int)*g->n);
for (bvgraph_nonzero_iterator(g, &iter);
bvgraph_iterator_valid(&iter);
bvgraph_iterator_next(&iter))
{
bvgraph_iterator_outedges(&iter, &links, &d);
for (i = 0; i < d; i++) {
colsum[links[i]]++;
}
}
bvgraph_iterator_free(&iter);
for (rep = 0; rep < 10000; rep++) {
memset(colsum2, 0, sizeof(int)*g->n);
for (bvgraph_nonzero_iterator(g, &iter);
bvgraph_iterator_valid(&iter);
bvgraph_iterator_next(&iter))
{
bvgraph_iterator_outedges(&iter, &links, &d);
for (i = 0; i < d; i++) {
colsum2[links[i]]++;
}
}
bvgraph_iterator_free(&iter);
for (i=0; i < g->n; i++) {
if (colsum2[i] != colsum[i]) {
fprintf(stderr, "error, column sum of column %i is not correct (%i =? %i)",
i, colsum[i], colsum2[i]);
perror("colsum error!");
}
}
}
free(colsum);
free(colsum2);
}
bvgraph_close(g);
for (i = 0; i < 10000000; i++) {
rval = bvgraph_load(g, filename, filenamelen, 0);
bvgraph_close(g);
}
}