# ISLocalToGlobalMapping

mappings from an arbitrary local ordering from 0 to n-1 to a global PETSc ordering used by a vector or matrix.

### Synopsis

    struct _p_ISLocalToGlobalMapping{
      PETSCHEADER(int)
      int n;                  /* number of local indices */
      int *indices;           /* global index of each local index */
      int globalstart;        /* first global referenced in indices */
      int globalend;          /* last + 1 global referenced in indices */
      int *globals;           /* local index for each global index between start and end */
    };

Note: mapping from Local to Global is scalable; but Global to Local may not be if the range of global values represented locally is very large.

Note: the ISLocalToGlobalMapping is actually a private object; it is included here for the MACRO ISLocalToGlobalMappingApply() to allow it to be inlined since it is used so often.

### See Also

ISLocalToGlobalMappingCreate()

Level:intermediate
Location: src/vec/is/../../../include/petscis.h
Index of all IS routines
Table of Contents for all manual pages
Index of all manual pages