xref: /petsc/include/petsc.h (revision 6c7c30d09ea650caf94ac3d94fba7aa580da96d8)
1 /* $Id: petsc.h,v 1.287 2001/04/10 22:37:51 balay Exp bsmith $ */
2 /*
3    This is the main PETSc include file (for C and C++).  It is included by all
4    other PETSc include files, so it almost never has to be specifically included.
5 */
6 #if !defined(__PETSC_H)
7 #define __PETSC_H
8 
9 /* ========================================================================== */
10 /*
11    Current PETSc version number and release date
12 */
13 #include "petscversion.h"
14 
15 /* ========================================================================== */
16 /*
17    The PETSc configuration file.  Contains various definitions that
18    handle portability issues and the presence of machine features.
19 
20    petscconf.h is contained in bmake/${PETSC_ARCH}/petscconf.h it is
21    found automatically by the compiler due to the -I${PETSC_DIR}/bmake/${PETSC_ARCH}
22    in the bmake/common_variables definition of PETSC_INCLUDE
23 */
24 #include "petscconf.h"
25 
26 /* ========================================================================== */
27 
28 #include <stdio.h>
29 /*
30     Defines the interface to MPI allowing the use of all MPI functions.
31 */
32 #include "mpi.h"
33 
34 /*
35     EXTERN indicates a PETSc function defined elsewhere
36 */
37 #define EXTERN extern
38 
39 /*
40     Defines some elementary mathematics functions and constants.
41 */
42 #include "petscmath.h"
43 
44 /*
45        Basic PETSc constants
46 */
47 
48 /*E
49     PetscTruth - Logical variable. Actually an integer
50 
51    Level: beginner
52 
53 E*/
54 typedef enum { PETSC_FALSE,PETSC_TRUE } PetscTruth;
55 
56 #define PETSC_NULL           0
57 #define PETSC_DECIDE         -1
58 #define PETSC_DEFAULT        -2
59 
60 #define PETSC_YES            PETSC_TRUE
61 #define PETSC_NO             PETSC_FALSE
62 #define PETSC_IGNORE         PETSC_NULL
63 #define PETSC_DETERMINE      PETSC_DECIDE
64 
65 
66 extern MPI_Comm   PETSC_COMM_WORLD;
67 extern MPI_Comm   PETSC_COMM_SELF;
68 extern PetscTruth PetscInitializeCalled;
69 EXTERN int        PetscSetCommWorld(MPI_Comm);
70 EXTERN int        PetscSetHelpVersionFunctions(int (*)(MPI_Comm),int (*)(MPI_Comm));
71 
72 /*MC
73    PetscMalloc - Allocates memory
74 
75    Input Parameter:
76 .  m - number of bytes to allocate
77 
78    Output Parameter:
79 .  result - memory allocated
80 
81    Synopsis:
82    int PetscMalloc(int m,void **result)
83 
84    Level: beginner
85 
86    Notes: Memory is always allocated at least double aligned
87 
88 .seealso: PetscFree(), PetscNew()
89 
90   Concepts: memory allocation
91 
92 M*/
93 #define PetscMalloc(a,b)     (*PetscTrMalloc)((a),__LINE__,__FUNCT__,__FILE__,__SDIR__,(void**)(b))
94 /*MC
95    PetscNew - Allocates memory of a particular type
96 
97    Input Parameter:
98 . type - structure name of space to be allocated. Memory of size sizeof(type) is allocated
99 
100    Output Parameter:
101 .  result - memory allocated
102 
103    Synopsis:
104    int PetscNew(struct type,((type *))result)
105 
106    Level: beginner
107 
108 .seealso: PetscFree(), PetscMalloc()
109 
110   Concepts: memory allocation
111 
112 M*/
113 #define PetscNew(A,b)        PetscMalloc(sizeof(A),(b))
114 /*MC
115    PetscFree - Frees memory
116 
117    Input Parameter:
118 .   memory - memory to free
119 
120    Synopsis:
121    int PetscFree(memory)
122 
123    Level: beginner
124 
125    Notes: Memory must have been obtained with PetscNew() or PetscMalloc()
126 
127 .seealso: PetscNew(), PetscMalloc()
128 
129   Concepts: memory allocation
130 
131 M*/
132 #define PetscFree(a)         (*PetscTrFree)((a),__LINE__,__FUNCT__,__FILE__,__SDIR__)
133 EXTERN int  (*PetscTrMalloc)(int,int,char*,char*,char*,void**);
134 EXTERN int  (*PetscTrFree)(void *,int,char*,char*,char*);
135 EXTERN int  PetscSetMalloc(int (*)(int,int,char*,char*,char*,void**),int (*)(void *,int,char*,char*,char*));
136 EXTERN int  PetscClearMalloc(void);
137 
138 /*
139    Routines for tracing memory corruption/bleeding with default PETSc
140    memory allocation
141 */
142 EXTERN int   PetscTrDump(FILE *);
143 EXTERN int   PetscTrSpace(PetscLogDouble *,PetscLogDouble *,PetscLogDouble *);
144 EXTERN int   PetscTrValid(int,const char[],const char[],const char[]);
145 EXTERN int   PetscTrDebugLevel(int);
146 EXTERN int   PetscTrLog(void);
147 EXTERN int   PetscTrLogDump(FILE *);
148 EXTERN int   PetscGetResidentSetSize(PetscLogDouble *);
149 
150 /*
151     Variable type where we stash PETSc object pointers in Fortran.
152     Assumes that sizeof(long) == sizeof(void*)which is true on
153     all machines that we know.
154 */
155 #define PetscFortranAddr   long
156 
157 /*E
158     PetscDataType - Used for handling different basic data types.
159 
160    Level: beginner
161 
162 .seealso: PetscBinaryRead(), PetscBinaryWrite(), PetscDataTypeToMPIDataType(),
163           PetscDataTypeGetSize(), PetscDataTypeGetName()
164 
165 E*/
166 typedef enum {PETSC_INT = 0,PETSC_DOUBLE = 1,PETSC_COMPLEX = 2,
167               PETSC_LONG =3 ,PETSC_SHORT = 4,PETSC_FLOAT = 5,
168               PETSC_CHAR = 6,PETSC_LOGICAL = 7} PetscDataType;
169 #if defined(PETSC_USE_COMPLEX)
170 #define PETSC_SCALAR PETSC_COMPLEX
171 #else
172 #define PETSC_SCALAR PETSC_DOUBLE
173 #endif
174 #if defined(PETSC_USE_SINGLE)
175 #define PETSC_REAL PETSC_FLOAT
176 #else
177 #define PETSC_REAL PETSC_DOUBLE
178 #endif
179 #define PETSC_FORTRANADDR PETSC_LONG
180 
181 EXTERN int PetscDataTypeToMPIDataType(PetscDataType,MPI_Datatype*);
182 EXTERN int PetscDataTypeGetSize(PetscDataType,int*);
183 EXTERN int PetscDataTypeGetName(PetscDataType,char*[]);
184 
185 /*
186     Basic memory and string operations. These are usually simple wrappers
187    around the basic Unix system calls, but a few of them have additional
188    functionality and/or error checking.
189 */
190 EXTERN int   PetscMemcpy(void *,const void *,int);
191 EXTERN int   PetscBitMemcpy(void*,int,const void*,int,int,PetscDataType);
192 EXTERN int   PetscMemmove(void *,void *,int);
193 EXTERN int   PetscMemzero(void *,int);
194 EXTERN int   PetscMemcmp(const void*,const void*,int,PetscTruth *);
195 EXTERN int   PetscStrlen(const char[],int*);
196 EXTERN int   PetscStrcmp(const char[],const char[],PetscTruth *);
197 EXTERN int   PetscStrgrt(const char[],const char[],PetscTruth *);
198 EXTERN int   PetscStrcasecmp(const char[],const char[],PetscTruth*);
199 EXTERN int   PetscStrncmp(const char[],const char[],int,PetscTruth*);
200 EXTERN int   PetscStrcpy(char[],const char[]);
201 EXTERN int   PetscStrcat(char[],const char[]);
202 EXTERN int   PetscStrncat(char[],const char[],int);
203 EXTERN int   PetscStrncpy(char[],const char[],int);
204 EXTERN int   PetscStrchr(const char[],char,char **);
205 EXTERN int   PetscStrtolower(char[]);
206 EXTERN int   PetscStrrchr(const char[],char,char **);
207 EXTERN int   PetscStrstr(const char[],const char[],char **);
208 EXTERN int   PetscStrtok(const char[],const char[],char **);
209 EXTERN int   PetscStrallocpy(const char[],char **);
210 EXTERN int   PetscStrreplace(MPI_Comm,const char[],char*,int);
211 #define      PetscStrfree(a) ((a) ? PetscFree(a) : 0)
212 
213 /*
214    These are  MPI operations for MPI_Allreduce() etc
215 */
216 EXTERN MPI_Op PetscMaxSum_Op;
217 #if defined(PETSC_USE_COMPLEX)
218 EXTERN MPI_Op PetscSum_Op;
219 #else
220 #define PetscSum_Op MPI_SUM
221 #endif
222 
223 /*
224   Each PETSc object class has it's own cookie (internal integer in the
225   data structure used for error checking). These are all defined by an offset
226   from the lowest one, PETSC_COOKIE.
227 */
228 #define PETSC_COOKIE                    1211211
229 #define PETSC_MAX_COOKIES               60
230 #define PETSC_LARGEST_COOKIE_PREDEFINED PETSC_COOKIE + 30
231 #define PETSC_LARGEST_COOKIE_ALLOWED    PETSC_COOKIE + PETSC_MAX_COOKIES
232 extern int PETSC_LARGEST_COOKIE;
233 
234 /*S
235      PetscObject - any PETSc object, PetscViewer, Mat, Vec, SLES etc
236 
237    Level: beginner
238 
239 .seealso:  PetscObjectDestroy(), PetscObjectView(), PetscObjectGetName(), PetscObjectSetName()
240 S*/
241 typedef struct _p_PetscObject* PetscObject;
242 
243 /*S
244      PetscFList - Linked list of functions, possibly stored in dynamic libraries, accessed
245       by string name
246 
247    Level: advanced
248 
249 .seealso:  PetscFListAdd(), PetscFListDestroy()
250 S*/
251 typedef struct _PetscFList *PetscFList;
252 
253 #include "petscviewer.h"
254 #include "petscoptions.h"
255 
256 EXTERN int PetscShowMemoryUsage(PetscViewer,char*);
257 EXTERN int PetscGetTime(PetscLogDouble*);
258 EXTERN int PetscGetCPUTime(PetscLogDouble*);
259 EXTERN int PetscSleep(int);
260 
261 /*
262     Initialization of PETSc
263 */
264 EXTERN int  PetscInitialize(int*,char***,char[],const char[]);
265 EXTERN int  PetscInitializeNoArguments(void);
266 EXTERN int  PetscFinalize(void);
267 EXTERN int  PetscInitializeFortran(void);
268 
269 /*
270     Functions that can act on any PETSc object.
271 */
272 EXTERN int PetscObjectDestroy(PetscObject);
273 EXTERN int PetscObjectExists(PetscObject,PetscTruth*);
274 EXTERN int PetscObjectGetComm(PetscObject,MPI_Comm *);
275 EXTERN int PetscObjectGetCookie(PetscObject,int *);
276 EXTERN int PetscObjectGetType(PetscObject,int *);
277 EXTERN int PetscObjectSetName(PetscObject,const char[]);
278 EXTERN int PetscObjectGetName(PetscObject,char*[]);
279 EXTERN int PetscObjectReference(PetscObject);
280 EXTERN int PetscObjectGetReference(PetscObject,int*);
281 EXTERN int PetscObjectDereference(PetscObject);
282 EXTERN int PetscObjectGetNewTag(PetscObject,int *);
283 EXTERN int PetscCommGetNewTag(MPI_Comm,int *);
284 EXTERN int PetscObjectView(PetscObject,PetscViewer);
285 EXTERN int PetscObjectCompose(PetscObject,const char[],PetscObject);
286 EXTERN int PetscObjectQuery(PetscObject,const char[],PetscObject *);
287 EXTERN int PetscObjectComposeFunction(PetscObject,const char[],const char[],void (*)());
288 #if defined(PETSC_USE_DYNAMIC_LIBRARIES)
289 #define PetscObjectComposeFunctionDynamic(a,b,c,d) PetscObjectComposeFunction(a,b,c,0)
290 #else
291 #define PetscObjectComposeFunctionDynamic(a,b,c,d) PetscObjectComposeFunction(a,b,c,(void (*)())(d))
292 #endif
293 EXTERN int PetscObjectQueryFunction(PetscObject,const char[],void (**)());
294 EXTERN int PetscObjectSetOptionsPrefix(PetscObject,const char[]);
295 EXTERN int PetscObjectAppendOptionsPrefix(PetscObject,const char[]);
296 EXTERN int PetscObjectPrependOptionsPrefix(PetscObject,const char[]);
297 EXTERN int PetscObjectGetOptionsPrefix(PetscObject,char*[]);
298 EXTERN int PetscObjectPublish(PetscObject);
299 EXTERN int PetscObjectChangeTypeName(PetscObject,char *);
300 EXTERN int PetscObjectRegisterDestroy(PetscObject);
301 EXTERN int PetscObjectRegisterDestroyAll(void);
302 EXTERN int PetscObjectName(PetscObject);
303 EXTERN int PetscTypeCompare(PetscObject,char*,PetscTruth*);
304 
305 /*
306     Defines PETSc error handling.
307 */
308 #include "petscerror.h"
309 
310 /*S
311      PetscOList - Linked list of PETSc objects, accessable by string name
312 
313    Level: advanced
314 
315 .seealso:  PetscOListAdd(), PetscOListDestroy(), PetscOListFind()
316 S*/
317 typedef struct _PetscOList *PetscOList;
318 
319 EXTERN int PetscOListDestroy(PetscOList *);
320 EXTERN int PetscOListFind(PetscOList,const char[],PetscObject*);
321 EXTERN int PetscOListReverseFind(PetscOList,PetscObject,char**);
322 EXTERN int PetscOListAdd(PetscOList *,const char[],PetscObject);
323 EXTERN int PetscOListDuplicate(PetscOList,PetscOList *);
324 
325 /*
326     Dynamic library lists. Lists of names of routines in dynamic
327   link libraries that will be loaded as needed.
328 */
329 EXTERN int PetscFListAdd(PetscFList*,const char[],const char[],void (*)());
330 EXTERN int PetscFListDestroy(PetscFList*);
331 EXTERN int PetscFListFind(MPI_Comm,PetscFList,const char[],void (**)());
332 EXTERN int PetscFListPrintTypes(MPI_Comm,FILE*,const char[],const char[],char *,char *,PetscFList);
333 #if defined(PETSC_USE_DYNAMIC_LIBRARIES)
334 #define    PetscFListAddDynamic(a,b,p,c) PetscFListAdd(a,b,p,0)
335 #else
336 #define    PetscFListAddDynamic(a,b,p,c) PetscFListAdd(a,b,p,(void (*)())c)
337 #endif
338 EXTERN int PetscFListDuplicate(PetscFList,PetscFList *);
339 EXTERN int PetscFListView(PetscFList,PetscViewer);
340 EXTERN int PetscFListConcat(const char [],const char [],char []);
341 EXTERN int PetscFListGet(PetscFList,char ***,int*);
342 
343 /*S
344      PetscDLLibraryList - Linked list of dynamics libraries to search for functions
345 
346    Level: advanced
347 
348    PETSC_USE_DYNAMIC_LIBRARIES must be defined in petscconf.h to use dynamic libraries
349 
350 .seealso:  PetscDLLibraryOpen()
351 S*/
352 typedef struct _PetscDLLibraryList *PetscDLLibraryList;
353 extern PetscDLLibraryList DLLibrariesLoaded;
354 EXTERN int PetscDLLibraryRetrieve(MPI_Comm,const char[],char *,int,PetscTruth *);
355 EXTERN int PetscDLLibraryOpen(MPI_Comm,const char[],void **);
356 EXTERN int PetscDLLibrarySym(MPI_Comm,PetscDLLibraryList *,const char[],const char[],void **);
357 EXTERN int PetscDLLibraryAppend(MPI_Comm,PetscDLLibraryList *,const char[]);
358 EXTERN int PetscDLLibraryPrepend(MPI_Comm,PetscDLLibraryList *,const char[]);
359 EXTERN int PetscDLLibraryClose(PetscDLLibraryList);
360 EXTERN int PetscDLLibraryPrintPath(void);
361 EXTERN int PetscDLLibraryGetInfo(void *,char *,char **);
362 
363 /*
364     Mechanism for translating PETSc object representations between languages
365     Not currently used.
366 */
367 typedef enum {PETSC_LANGUAGE_C,PETSC_LANGUAGE_CPP} PetscLanguage;
368 #define PETSC_LANGUAGE_F77 PETSC_LANGUAGE_C
369 EXTERN int PetscObjectComposeLanguage(PetscObject,PetscLanguage,void *);
370 EXTERN int PetscObjectQueryLanguage(PetscObject,PetscLanguage,void **);
371 
372 /*
373      Useful utility routines
374 */
375 EXTERN int PetscSplitOwnership(MPI_Comm,int*,int*);
376 EXTERN int PetscSplitOwnershipBlock(MPI_Comm,int,int*,int*);
377 EXTERN int PetscSequentialPhaseBegin(MPI_Comm,int);
378 EXTERN int PetscSequentialPhaseEnd(MPI_Comm,int);
379 EXTERN int PetscBarrier(PetscObject);
380 EXTERN int PetscMPIDump(FILE*);
381 
382 #define PetscNot(a) ((a) ? PETSC_FALSE : PETSC_TRUE)
383 /*
384     Defines basic graphics available from PETSc.
385 */
386 #include "petscdraw.h"
387 
388 /*
389     Defines the base data structures for all PETSc objects
390 */
391 #include "petschead.h"
392 
393 /*
394      Defines PETSc profiling.
395 */
396 #include "petsclog.h"
397 
398 /*
399           For locking, unlocking and destroying AMS memories associated with
400     PETSc objects
401 */
402 #if defined(PETSC_HAVE_AMS)
403 
404 extern PetscTruth PetscAMSPublishAll;
405 #define PetscPublishAll(v) (PetscAMSPublishAll ? PetscObjectPublish((PetscObject)v) : 0)
406 #define PetscObjectTakeAccess(obj)  ((((PetscObject)(obj))->amem == -1) ? 0 : AMS_Memory_take_access(((PetscObject)(obj))->amem))
407 #define PetscObjectGrantAccess(obj) ((((PetscObject)(obj))->amem == -1) ? 0 : AMS_Memory_grant_access(((PetscObject)(obj))->amem))
408 #define PetscObjectDepublish(obj)   ((((PetscObject)(obj))->amem == -1) ? 0 : AMS_Memory_destroy(((PetscObject)(obj))->amem)); \
409     ((PetscObject)(obj))->amem = -1;
410 
411 #else
412 
413 #define PetscPublishAll(v)           0
414 #define PetscObjectTakeAccess(obj)   0
415 #define PetscObjectGrantAccess(obj)  0
416 #define PetscObjectDepublish(obj)      0
417 
418 #endif
419 
420 
421 
422 /*
423       This code allows one to pass a MPI communicator between
424     C and Fortran. MPI 2.0 defines a standard API for doing this.
425     The code here is provided to allow PETSc to work with MPI 1.1
426     standard MPI libraries.
427 */
428 EXTERN int  MPICCommToFortranComm(MPI_Comm,int *);
429 EXTERN int  MPIFortranCommToCComm(int,MPI_Comm*);
430 
431 /*
432       Simple PETSc parallel IO for ASCII printing
433 */
434 EXTERN int  PetscFixFilename(const char[],char[]);
435 EXTERN int  PetscFOpen(MPI_Comm,const char[],const char[],FILE**);
436 EXTERN int  PetscFClose(MPI_Comm,FILE*);
437 EXTERN int  PetscFPrintf(MPI_Comm,FILE*,const char[],...);
438 EXTERN int  PetscPrintf(MPI_Comm,const char[],...);
439 EXTERN int  (*PetscErrorPrintf)(const char[],...);
440 EXTERN int  (*PetscHelpPrintf)(MPI_Comm,const char[],...);
441 EXTERN int  PetscPOpen(MPI_Comm,char *,char*,const char[],FILE **);
442 EXTERN int  PetscPClose(MPI_Comm,FILE*);
443 EXTERN int  PetscSynchronizedPrintf(MPI_Comm,const char[],...);
444 EXTERN int  PetscSynchronizedFPrintf(MPI_Comm,FILE*,const char[],...);
445 EXTERN int  PetscSynchronizedFlush(MPI_Comm);
446 EXTERN int  PetscSynchronizedFGets(MPI_Comm,FILE*,int,char[]);
447 EXTERN int  PetscStartMatlab(MPI_Comm,char *,char*,FILE**);
448 EXTERN int  PetscStartJava(MPI_Comm,char *,char*,FILE**);
449 
450 EXTERN int  PetscPopUpSelect(MPI_Comm,char*,char*,int,char**,int*);
451 /*S
452      PetscObjectContainer - Simple PETSc object that contains a pointer to any required data
453 
454    Level: advanced
455 
456 .seealso:  PetscObject, PetscObjectContainerCreate()
457 S*/
458 typedef struct _p_PetscObjectContainer*  PetscObjectContainer;
459 EXTERN int PetscObjectContainerGetPointer(PetscObjectContainer,void **);
460 EXTERN int PetscObjectContainerSetPointer(PetscObjectContainer,void *);
461 EXTERN int PetscObjectContainerDestroy(PetscObjectContainer);
462 EXTERN int PetscObjectContainerCreate(MPI_Comm comm,PetscObjectContainer *);
463 
464 /*
465    For incremental debugging
466 */
467 extern PetscTruth PetscCompare;
468 EXTERN int        PetscCompareDouble(double);
469 EXTERN int        PetscCompareScalar(Scalar);
470 EXTERN int        PetscCompareInt(int);
471 
472 /*
473    For use in debuggers
474 */
475 extern int PetscGlobalRank,PetscGlobalSize;
476 EXTERN int PetscIntView(int,int[],PetscViewer);
477 EXTERN int PetscDoubleView(int,double[],PetscViewer);
478 EXTERN int PetscScalarView(int,Scalar[],PetscViewer);
479 
480 /*
481     Allows accessing Matlab Engine
482 */
483 #include "petscengine.h"
484 
485 /*
486     C code optimization is often enhanced by telling the compiler
487   that certain pointer arguments to functions are not aliased to
488   to other arguments. This is not yet ANSI C standard so we define
489   the macro "restrict" to indicate that the variable is not aliased
490   to any other argument.
491 */
492 #if defined(PETSC_HAVE_RESTRICT) && !defined(__cplusplus)
493 #define restrict _Restrict
494 #else
495 #define restrict
496 #endif
497 
498 /*
499       Determine if some of the kernel computation routines use
500    Fortran (rather than C) for the numerical calculations. On some machines
501    and compilers (like complex numbers) the Fortran version of the routines
502    is faster than the C/C++ versions. The flag PETSC_USE_FORTRAN_KERNELS
503    would be set in the petscconf.h file
504 */
505 #if defined(PETSC_USE_FORTRAN_KERNELS)
506 
507 #if !defined(PETSC_USE_FORTRAN_KERNEL_MULTAIJ)
508 #define PETSC_USE_FORTRAN_KERNEL_MULTAIJ
509 #endif
510 
511 #if !defined(PETSC_USE_FORTRAN_KERNEL_NORMSQR)
512 #define PETSC_USE_FORTRAN_KERNEL_NORMSQR
513 #endif
514 
515 #if !defined(PETSC_USE_FORTRAN_KERNEL_MAXPY)
516 #define PETSC_USE_FORTRAN_KERNEL_MAXPY
517 #endif
518 
519 #if !defined(PETSC_USE_FORTRAN_KERNEL_SOLVEAIJ)
520 #define PETSC_USE_FORTRAN_KERNEL_SOLVEAIJ
521 #endif
522 
523 #if !defined(PETSC_USE_FORTRAN_KERNEL_SOLVEBAIJ)
524 #define PETSC_USE_FORTRAN_KERNEL_SOLVEBAIJ
525 #endif
526 
527 #if !defined(PETSC_USE_FORTRAN_KERNEL_MULTADDAIJ)
528 #define PETSC_USE_FORTRAN_KERNEL_MULTADDAIJ
529 #endif
530 
531 #if !defined(PETSC_USE_FORTRAN_KERNEL_MDOT)
532 #define PETSC_USE_FORTRAN_KERNEL_MDOT
533 #endif
534 
535 #if !defined(PETSC_USE_FORTRAN_KERNEL_XTIMESY)
536 #define PETSC_USE_FORTRAN_KERNEL_XTIMESY
537 #endif
538 
539 #endif
540 
541 /*
542     Macros for indicating code that should be compiled with a C interface,
543    rather than a C++ interface. Any routines that are dynamically loaded
544    (such as the PCCreate_XXX() routines) must be wrapped so that the name
545    mangler does not change the functions symbol name. This just hides the
546    ugly extern "C" {} wrappers.
547 */
548 #if defined(__cplusplus)
549 #define EXTERN_C_BEGIN extern "C" {
550 #define EXTERN_C_END }
551 #else
552 #define EXTERN_C_BEGIN
553 #define EXTERN_C_END
554 #endif
555 
556 /* --------------------------------------------------------------------*/
557 /*
558     DVF (win32) uses STDCALL calling convention by default.
559     The following is used by the fortran interface.
560 */
561 #if defined (PETSC_USE_FORTRAN_STDCALL)
562 #define PETSC_STDCALL __stdcall
563 #else
564 #define PETSC_STDCALL
565 #endif
566 
567 #endif
568 
569 /*M
570     size - integer variable used to contain the number of processors in
571            the relevent MPI_Comm
572 
573    Level: beginner
574 
575 .seealso: rank, comm
576 M*/
577 
578 /*M
579     rank - integer variable used to contain the number of this processor relative
580            to all in the relevent MPI_Comm
581 
582    Level: beginner
583 
584 .seealso: size, comm
585 M*/
586 
587 /*M
588     comm - MPI_Comm used in the current routine or object
589 
590    Level: beginner
591 
592 .seealso: size, rank
593 M*/
594 
595 /*M
596     Scalar - PETSc type that represents either a double precision real number or
597        a double precision complex number if the code is compiled with BOPT=g_complex or O_complex
598 
599    Level: beginner
600 
601 M*/
602 
603 /*
604      The IBM include files define hz, here we hide it so that it may be used
605    as a regular user variable.
606 */
607 #if defined(hz)
608 #undef hz
609 #endif
610