2:  #include <petsc/private/isimpl.h>

  4: PetscFunctionList ISList              = NULL;
  5: PetscBool         ISRegisterAllCalled = PETSC_FALSE;

  7: /*@
  8:    ISCreate - Creates an index set object.

 10:    Collective on MPI_Comm

 12:    Input Parameters:
 13: .  comm - the MPI communicator

 15:    Output Parameter:
 16: .  is - the new index set

 18:    Notes:
 19:    When the communicator is not MPI_COMM_SELF, the operations on IS are NOT
 20:    conceptually the same as MPI_Group operations. The IS are then
 21:    distributed sets of indices and thus certain operations on them are
 22:    collective.

 24:    Level: beginner

 26:   Concepts: index sets^creating
 27:   Concepts: IS^creating

 29: .seealso: ISCreateGeneral(), ISCreateStride(), ISCreateBlock(), ISAllGather()
 30: @*/
 31: PetscErrorCode  ISCreate(MPI_Comm comm,IS *is)
 32: {

 37:   ISInitializePackage();

 39:   PetscHeaderCreate(*is,IS_CLASSID,"IS","Index Set","IS",comm,ISDestroy,ISView);
 40:   PetscLayoutCreate(comm, &(*is)->map);
 41:   return(0);
 42: }

 44: /*@C
 45:   ISSetType - Builds a index set, for a particular implementation.

 47:   Collective on IS

 49:   Input Parameters:
 50: + is    - The index set object
 51: - method - The name of the index set type

 53:   Options Database Key:
 54: . -is_type <type> - Sets the index set type; use -help for a list of available types

 56:   Notes:
 57:   See "petsc/include/petscis.h" for available istor types (for instance, ISGENERAL, ISSTRIDE, or ISBLOCK).

 59:   Use ISDuplicate() to make a duplicate

 61:   Level: intermediate


 64: .seealso: ISGetType(), ISCreate()
 65: @*/
 66: PetscErrorCode  ISSetType(IS is, ISType method)
 67: {
 68:   PetscErrorCode (*r)(IS);
 69:   PetscBool      match;

 74:   PetscObjectTypeCompare((PetscObject) is, method, &match);
 75:   if (match) return(0);

 77:   ISRegisterAll();
 78:   PetscFunctionListFind(ISList,method,&r);
 79:   if (!r) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_UNKNOWN_TYPE, "Unknown IS type: %s", method);
 80:   if (is->ops->destroy) {
 81:     (*is->ops->destroy)(is);
 82:     is->ops->destroy = NULL;
 83:   }
 84:   (*r)(is);
 85:   PetscObjectChangeTypeName((PetscObject)is,method);
 86:   return(0);
 87: }

 89: /*@C
 90:   ISGetType - Gets the index set type name (as a string) from the IS.

 92:   Not Collective

 94:   Input Parameter:
 95: . is  - The index set

 97:   Output Parameter:
 98: . type - The index set type name

100:   Level: intermediate

102: .seealso: ISSetType(), ISCreate()
103: @*/
104: PetscErrorCode  ISGetType(IS is, ISType *type)
105: {

111:   if (!ISRegisterAllCalled) {
112:     ISRegisterAll();
113:   }
114:   *type = ((PetscObject)is)->type_name;
115:   return(0);
116: }


119: /*--------------------------------------------------------------------------------------------------------------------*/

121: /*@C
122:   ISRegister - Adds a new index set implementation

124:   Not Collective

126:   Input Parameters:
127: + name        - The name of a new user-defined creation routine
128: - create_func - The creation routine itself

130:   Notes:
131:   ISRegister() may be called multiple times to add several user-defined vectors

133:   Sample usage:
134: .vb
135:     ISRegister("my_is_name",  MyISCreate);
136: .ve

138:   Then, your vector type can be chosen with the procedural interface via
139: .vb
140:     ISCreate(MPI_Comm, IS *);
141:     ISSetType(IS,"my_is_name");
142: .ve
143:    or at runtime via the option
144: .vb
145:     -is_type my_is_name
146: .ve

148:   This is no ISSetFromOptions() and the current implementations do not have a way to dynamically determine type, so
149:   dynamic registration of custom IS types will be of limited use to users.

151:   Level: developer

153: .keywords: IS, register
154: .seealso: ISRegisterAll(), ISRegisterDestroy(), ISRegister()

156:   Level: advanced
157: @*/
158: PetscErrorCode  ISRegister(const char sname[], PetscErrorCode (*function)(IS))
159: {

163:   PetscFunctionListAdd(&ISList,sname,function);
164:   return(0);
165: }