Date: 2026-03-31T13:23:10+00:00

Actual source code: network.c

      1: /*
      2:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
      3:    SLEPc - Scalable Library for Eigenvalue Problem Computations
      4:    Copyright (c) 2002-, Universitat Politecnica de Valencia, Spain

      6:    This file is part of SLEPc.
      7:    SLEPc is distributed under a 2-clause BSD license (see LICENSE).
      8:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
      9: */

     11: #include "network.h"

     13: const char *GraphTypes[] = {"sym","asym","bip",NULL};
     14: const char *GraphWeights[] = {"unweighted","positive","posweighted","signed","multisigned","weighted","multiweighted","dynamic","multiposweighted",NULL};

     16: PetscErrorCode GraphCreate(MPI_Comm comm,Graph *graph)
     17: {
     18:   PetscFunctionBeginUser;
     19:   PetscCall(PetscNew(graph));
     20:   (*graph)->comm = comm;
     21:   PetscFunctionReturn(PETSC_SUCCESS);
     22: }

     24: PetscErrorCode GraphDestroy(Graph *graph)
     25: {
     26:   PetscFunctionBeginUser;
     27:   if (!*graph) PetscFunctionReturn(PETSC_SUCCESS);
     28:   PetscCall(MatDestroy(&((*graph)->adjacency)));
     29:   PetscCall(PetscFree(*graph));
     30:   PetscFunctionReturn(PETSC_SUCCESS);
     31: }

     33: PetscErrorCode GraphPreload(Graph graph,char *filename)
     34: {
     35:   PetscInt    i,nval,src,dst;
     36:   PetscBool   flg;
     37:   PetscMPIInt rank;
     38:   FILE        *file;
     39:   char        gtype[64],gweight[64],line[PETSC_MAX_PATH_LEN];

     41:   PetscFunctionBeginUser;
     42:   PetscCallMPI(MPI_Comm_rank(graph->comm,&rank));
     43:   if (rank==0) {
     44:     PetscCall(PetscFOpen(PETSC_COMM_SELF,filename,"r",&file));
     45:     /* process first line of the file */
     46:     nval = fscanf(file,"%%%s%s\n",gtype,gweight);
     47:     PetscCheck(nval==2,PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"Badly formatted input file");
     48:     for (i=0;i<(int)sizeof(GraphTypes);i++) {
     49:       PetscCheck(GraphTypes[i],PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"Unknown graph type %s",gtype);
     50:       PetscCall(PetscStrcmp(gtype,GraphTypes[i],&flg));
     51:       if (flg) { graph->type = (GraphType)i; break; }
     52:     }
     53:     for (i=0;i<(int)sizeof(GraphWeights);i++) {
     54:       PetscCheck(GraphWeights[i],PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"Unknown graph weight %s",gweight);
     55:       PetscCall(PetscStrcmp(gweight,GraphWeights[i],&flg));
     56:       if (flg) { graph->weight = (GraphWeight)i; break; }
     57:     }
     58:     /* skip second line of the file if it is a comment */
     59:     if (!fgets(line,PETSC_MAX_PATH_LEN,file)) line[0] = 0;
     60:     if (line[0]=='%') {
     61:       if (!fgets(line,PETSC_MAX_PATH_LEN,file)) line[0] = 0;
     62:     }
     63:     graph->nedges = 1;
     64:     nval = sscanf(line,"%" PetscInt_FMT "%" PetscInt_FMT,&src,&dst);
     65:     PetscCheck(nval==2,PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"Badly formatted input file");
     66:     graph->nvertices = PetscMax(src,dst);
     67:     /* read rest of file to count lines */
     68:     while (fgets(line,PETSC_MAX_PATH_LEN,file)) {
     69:       nval = sscanf(line,"%" PetscInt_FMT "%" PetscInt_FMT,&src,&dst);
     70:       PetscCheck(nval==2,PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"Badly formatted input file");
     71:       graph->nedges++;
     72:       graph->nvertices = PetscMax(graph->nvertices,PetscMax(src,dst));
     73:     }
     74:     PetscCall(PetscFClose(PETSC_COMM_SELF,file));
     75:   }
     76:   PetscCallMPI(MPI_Bcast(&graph->type,1,MPIU_INT,0,PETSC_COMM_WORLD));
     77:   PetscCallMPI(MPI_Bcast(&graph->weight,1,MPIU_INT,0,PETSC_COMM_WORLD));
     78:   PetscCallMPI(MPI_Bcast(&graph->nvertices,1,MPIU_INT,0,PETSC_COMM_WORLD));
     79:   PetscCallMPI(MPI_Bcast(&graph->nedges,1,MPIU_INT,0,PETSC_COMM_WORLD));
     80:   PetscFunctionReturn(PETSC_SUCCESS);
     81: }

     83: PetscErrorCode GraphPreallocate(Graph graph,char *filename)
     84: {
     85:   PetscInt i,nval,src,dst,Istart,Iend,*d_nnz,*o_nnz;
     86:   FILE     *file;
     87:   char     line[PETSC_MAX_PATH_LEN];

     89:   PetscFunctionBeginUser;
     90:   PetscCheck(graph->nvertices,PETSC_COMM_SELF,PETSC_ERR_ORDER,"Must call GraphPreload() first");
     91:   PetscCall(MatDestroy(&graph->adjacency));
     92:   PetscCall(MatCreate(graph->comm,&graph->adjacency));
     93:   PetscCall(MatSetSizes(graph->adjacency,PETSC_DECIDE,PETSC_DECIDE,graph->nvertices,graph->nvertices));
     94:   PetscCall(MatSetType(graph->adjacency,MATAIJ));
     95:   PetscCall(MatGetOwnershipRange(graph->adjacency,&Istart,&Iend));
     96:   PetscCall(PetscCalloc2(Iend-Istart,&d_nnz,Iend-Istart,&o_nnz));

     98:   /* all process read the file */
     99:   PetscCall(PetscFOpen(PETSC_COMM_SELF,filename,"r",&file));
    100:   nval = fscanf(file,"%%%*s%*s\n");   /* first line of the file */
    101:   if (!fgets(line,PETSC_MAX_PATH_LEN,file)) line[0] = 0;
    102:   if (line[0]=='%') { /* skip second line of the file if it is a comment */
    103:     if (!fgets(line,PETSC_MAX_PATH_LEN,file)) line[0] = 0;
    104:   }
    105:   nval = sscanf(line,"%" PetscInt_FMT "%" PetscInt_FMT,&src,&dst);
    106:   PetscCheck(nval==2,PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"Badly formatted input file");
    107:   src--; dst--;     /* adjust from 1-based to 0-based */
    108:   if (src>=Istart && src<Iend) {
    109:     if (dst>=Istart && dst<Iend) d_nnz[src-Istart]++;
    110:     else o_nnz[src-Istart]++;
    111:   }
    112:   /* read rest of file */
    113:   while (fgets(line,PETSC_MAX_PATH_LEN,file)) {
    114:     nval = sscanf(line,"%" PetscInt_FMT "%" PetscInt_FMT,&src,&dst);
    115:     PetscCheck(nval==2,PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"Badly formatted input file");
    116:     src--; dst--;     /* adjust from 1-based to 0-based */
    117:     if (src>=Istart && src<Iend) {
    118:       if (dst>=Istart && dst<Iend) d_nnz[src-Istart]++;
    119:       else o_nnz[src-Istart]++;
    120:     }
    121:   }
    122:   PetscCall(PetscFClose(PETSC_COMM_SELF,file));

    124:   for (i=Istart;i<Iend;i++) d_nnz[i-Istart]++;  /* diagonal entries */
    125:   PetscCall(MatSeqAIJSetPreallocation(graph->adjacency,0,d_nnz));
    126:   PetscCall(MatMPIAIJSetPreallocation(graph->adjacency,0,d_nnz,0,o_nnz));
    127:   PetscCall(PetscFree2(d_nnz,o_nnz));
    128:   PetscFunctionReturn(PETSC_SUCCESS);
    129: }

    131: PetscErrorCode GraphLoadUnweighted(Graph graph,char *filename)
    132: {
    133:   PetscInt i,nval,src,dst,Istart,Iend;
    134:   FILE     *file;
    135:   char     line[PETSC_MAX_PATH_LEN];

    137:   PetscFunctionBeginUser;
    138:   PetscCheck(graph->adjacency,PETSC_COMM_SELF,PETSC_ERR_ORDER,"Must call GraphPreallocate() first");
    139:   PetscCall(MatGetOwnershipRange(graph->adjacency,&Istart,&Iend));
    140:   /* all process read the file */
    141:   PetscCall(PetscFOpen(PETSC_COMM_SELF,filename,"r",&file));
    142:   nval = fscanf(file,"%%%*s%*s\n");   /* first line of the file */
    143:   if (!fgets(line,PETSC_MAX_PATH_LEN,file)) line[0] = 0;
    144:   if (line[0]=='%') { /* skip second line of the file if it is a comment */
    145:     if (!fgets(line,PETSC_MAX_PATH_LEN,file)) line[0] = 0;
    146:   }
    147:   nval = sscanf(line,"%" PetscInt_FMT "%" PetscInt_FMT,&src,&dst);
    148:   PetscCheck(nval==2,PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"Badly formatted input file");
    149:   src--; dst--;     /* adjust from 1-based to 0-based */
    150:   if (src>=Istart && src<Iend) PetscCall(MatSetValue(graph->adjacency,src,dst,1.0,INSERT_VALUES));
    151:   /* read rest of file */
    152:   while (fgets(line,PETSC_MAX_PATH_LEN,file)) {
    153:     nval = sscanf(line,"%" PetscInt_FMT "%" PetscInt_FMT,&src,&dst);
    154:     PetscCheck(nval==2,PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"Badly formatted input file");
    155:     src--; dst--;     /* adjust from 1-based to 0-based */
    156:     if (src>=Istart && src<Iend) PetscCall(MatSetValue(graph->adjacency,src,dst,1.0,INSERT_VALUES));
    157:   }
    158:   PetscCall(PetscFClose(PETSC_COMM_SELF,file));
    159:   for (i=Istart;i<Iend;i++) PetscCall(MatSetValue(graph->adjacency,i,i,0.0,INSERT_VALUES));  /* diagonal entries */
    160:   PetscCall(MatAssemblyBegin(graph->adjacency,MAT_FINAL_ASSEMBLY));
    161:   PetscCall(MatAssemblyEnd(graph->adjacency,MAT_FINAL_ASSEMBLY));
    162:   PetscFunctionReturn(PETSC_SUCCESS);
    163: }