Actual source code: aosetlocal.c

 2:  #include petscao.h

  6: /*@C     
  7:        AODataPartitionAndSetupLocal - Partitions across a given key (for example cells), then partitions a segment
  8:          (for example vertices) subservient to that key.

 10:     Collective on AOData

 12:   Input Parameters:
 13: +  ao           - the AO database
 14: .  keyname      - the name of the key
 15: -  segmentname  - the name of the segment 


 18:   Output Parameters:
 19: +  iskey         - the local indices in global numbering of the key entries (cells). Note that these are
 20:                          contiguous from rstart to rend
 21: .  issegment     - the local indices in global numbering of the segment entries (vertices)
 22: -  ltog          - the local to global mapping for the segment entries (vertices)

 24:   Level: advanced

 26:   Notes: this renumbers the key and segment entries in the AO database to reflect the new partitioning.
 27:   The ltog mapping is a mapping for the issegment indices, that is ltog applied to the indices
 28:   0 to sizeof(issegment)-1 is the entries in issegment. 

 30: .seealso: AODataKeyParition(), AODataSegmentPartition()
 31: @*/
 32: PetscErrorCode AODataPartitionAndSetupLocal(AOData ao,const char keyname[],const char segmentname[],IS *iskey,IS *issegment,ISLocalToGlobalMapping *ltog)
 33: {
 34:   ISLocalToGlobalMapping ltogkey;
 35:   PetscErrorCode         ierr;
 36:   PetscInt               rstart,rend;
 37:   MPI_Comm               comm;


 41:   /*      Partition the keys (cells)   */
 42:   AODataKeyPartition(ao,keyname);

 44:   /*      Partition the segment (vertices) subservient to the keys (cells)  */
 45:   AODataSegmentPartition(ao,keyname,segmentname);

 47:  /*     Generate the list of key entries (cells) on this processor   */
 48:   AODataKeyGetOwnershipRange(ao,"cell",&rstart,&rend);
 49:   PetscObjectGetComm((PetscObject)ao,&comm);

 51:   ISCreateStride(comm,rend-rstart,rstart,1,iskey);

 53:  /*       Get the list of segment entries (vertices) used by these key entries (cells)   */
 54:   AODataSegmentGetReducedIS(ao,keyname,segmentname,*iskey,issegment);

 56:  /*     Make local to global mapping of key entries (cells)  */
 57:   ISLocalToGlobalMappingCreateIS(*iskey,&ltogkey);

 59:   /*       Make local to global mapping of segment entries (vertices)  */
 60:   ISLocalToGlobalMappingCreateIS(*issegment,ltog);

 62:   /*        Attach the local to global mappings to the database */
 63:   AODataKeySetLocalToGlobalMapping(ao,keyname,ltogkey);
 64:   AODataKeySetLocalToGlobalMapping(ao,segmentname,*ltog);

 66:   /*      Dereference the ltogkey; we don't need a copy of it */
 67:   PetscObjectDereference((PetscObject)ltogkey);

 69:   return(0);
 70: }