xref: /petsc/include/petscsystypes.h (revision 5440e5dcf30153d9ab6dbf994494f40b7f9df88b)
1 /* Portions of this code are under:
2    Copyright (c) 2022 Advanced Micro Devices, Inc. All rights reserved.
3 */
4 
5 #pragma once
6 
7 #include <petscconf.h>
8 #include <petscconf_poison.h>
9 #include <petscfix.h>
10 #include <petscmacros.h> // PETSC_NODISCARD, PETSC_CPP_VERSION
11 #include <stddef.h>
12 #include <stdbool.h>
13 
14 /* SUBMANSEC = Sys */
15 
16 #include <limits.h> // INT_MIN, INT_MAX, CHAR_BIT
17 
18 #if defined(__clang__) || (PETSC_CPP_VERSION >= 17)
19   // clang allows both [[nodiscard]] and __attribute__((warn_unused_result)) on type
20   // definitions. GCC, however, does not, so check that we are using C++17 [[nodiscard]]
21   // instead of __attribute__((warn_unused_result))
22   #define PETSC_ERROR_CODE_NODISCARD PETSC_NODISCARD
23 #else
24   #define PETSC_ERROR_CODE_NODISCARD
25 #endif
26 
27 #ifdef PETSC_CLANG_STATIC_ANALYZER
28   #undef PETSC_USE_STRICT_PETSCERRORCODE
29 #endif
30 
31 #ifdef PETSC_USE_STRICT_PETSCERRORCODE
32   #define PETSC_ERROR_CODE_TYPEDEF   typedef
33   #define PETSC_ERROR_CODE_ENUM_NAME PetscErrorCode
34 #else
35   #define PETSC_ERROR_CODE_TYPEDEF
36   #define PETSC_ERROR_CODE_ENUM_NAME
37 #endif
38 
39 /*E
40   PetscErrorCode - Datatype used to return PETSc error codes.
41 
42   Level: beginner
43 
44   Notes:
45   Virtually all PETSc functions return an error code. It is the callers responsibility to check
46   the value of the returned error code after each PETSc call to determine if any errors
47   occurred. A set of convenience macros (e.g. `PetscCall()`, `PetscCallVoid()`) are provided
48   for this purpose. Failing to properly check for errors is not supported, as errors may leave
49   PETSc in an undetermined state.
50 
51   One can retrieve the error string corresponding to a particular error code using
52   `PetscErrorMessage()`.
53 
54   The user can also configure PETSc with the `--with-strict-petscerrorcode` option to enable
55   compiler warnings when the returned error codes are not captured and checked. Users are
56   *heavily* encouraged to opt-in to this option, as it will become enabled by default in a
57   future release.
58 
59   Developer Notes:
60   These are the generic error codes. These error codes are used in many different places in the
61   PETSc source code. The C-string versions are at defined in `PetscErrorStrings[]` in
62   `src/sys/error/err.c`, while the Fortran versions are defined in
63   `src/sys/ftn-mod/petscerror.h`. Any changes here must also be made in both locations.
64 
65 .seealso: `PetscErrorMessage()`, `PetscCall()`, `SETERRQ()`
66 E*/
67 PETSC_ERROR_CODE_TYPEDEF enum PETSC_ERROR_CODE_NODISCARD {
68   PETSC_SUCCESS                   = 0,
69   PETSC_ERR_BOOLEAN_MACRO_FAILURE = 1, /* do not use */
70 
71   PETSC_ERR_MIN_VALUE = 54, /* should always be one less than the smallest value */
72 
73   PETSC_ERR_MEM            = 55, /* unable to allocate requested memory */
74   PETSC_ERR_SUP            = 56, /* no support for requested operation */
75   PETSC_ERR_SUP_SYS        = 57, /* no support for requested operation on this computer system */
76   PETSC_ERR_ORDER          = 58, /* operation done in wrong order */
77   PETSC_ERR_SIG            = 59, /* signal received */
78   PETSC_ERR_FP             = 72, /* floating point exception */
79   PETSC_ERR_COR            = 74, /* corrupted PETSc object */
80   PETSC_ERR_LIB            = 76, /* error in library called by PETSc */
81   PETSC_ERR_PLIB           = 77, /* PETSc library generated inconsistent data */
82   PETSC_ERR_MEMC           = 78, /* memory corruption */
83   PETSC_ERR_CONV_FAILED    = 82, /* iterative method (KSP or SNES) failed */
84   PETSC_ERR_USER           = 83, /* user has not provided needed function */
85   PETSC_ERR_SYS            = 88, /* error in system call */
86   PETSC_ERR_POINTER        = 70, /* pointer does not point to valid address */
87   PETSC_ERR_MPI_LIB_INCOMP = 87, /* MPI library at runtime is not compatible with MPI user compiled with */
88 
89   PETSC_ERR_ARG_SIZ          = 60, /* nonconforming object sizes used in operation */
90   PETSC_ERR_ARG_IDN          = 61, /* two arguments not allowed to be the same */
91   PETSC_ERR_ARG_WRONG        = 62, /* wrong argument (but object probably ok) */
92   PETSC_ERR_ARG_CORRUPT      = 64, /* null or corrupted PETSc object as argument */
93   PETSC_ERR_ARG_OUTOFRANGE   = 63, /* input argument, out of range */
94   PETSC_ERR_ARG_BADPTR       = 68, /* invalid pointer argument */
95   PETSC_ERR_ARG_NOTSAMETYPE  = 69, /* two args must be same object type */
96   PETSC_ERR_ARG_NOTSAMECOMM  = 80, /* two args must be same communicators */
97   PETSC_ERR_ARG_WRONGSTATE   = 73, /* object in argument is in wrong state, e.g. unassembled mat */
98   PETSC_ERR_ARG_TYPENOTSET   = 89, /* the type of the object has not yet been set */
99   PETSC_ERR_ARG_INCOMP       = 75, /* two arguments are incompatible */
100   PETSC_ERR_ARG_NULL         = 85, /* argument is null that should not be */
101   PETSC_ERR_ARG_UNKNOWN_TYPE = 86, /* type name doesn't match any registered type */
102 
103   PETSC_ERR_FILE_OPEN       = 65, /* unable to open file */
104   PETSC_ERR_FILE_READ       = 66, /* unable to read from file */
105   PETSC_ERR_FILE_WRITE      = 67, /* unable to write to file */
106   PETSC_ERR_FILE_UNEXPECTED = 79, /* unexpected data in file */
107 
108   PETSC_ERR_MAT_LU_ZRPVT = 71, /* detected a zero pivot during LU factorization */
109   PETSC_ERR_MAT_CH_ZRPVT = 81, /* detected a zero pivot during Cholesky factorization */
110 
111   PETSC_ERR_INT_OVERFLOW   = 84,
112   PETSC_ERR_FLOP_COUNT     = 90,
113   PETSC_ERR_NOT_CONVERGED  = 91,  /* solver did not converge */
114   PETSC_ERR_MISSING_FACTOR = 92,  /* MatGetFactor() failed */
115   PETSC_ERR_OPT_OVERWRITE  = 93,  /* attempted to over write options which should not be changed */
116   PETSC_ERR_WRONG_MPI_SIZE = 94,  /* example/application run with number of MPI ranks it does not support */
117   PETSC_ERR_USER_INPUT     = 95,  /* missing or incorrect user input */
118   PETSC_ERR_GPU_RESOURCE   = 96,  /* unable to load a GPU resource, for example cuBLAS */
119   PETSC_ERR_GPU            = 97,  /* An error from a GPU call, this may be due to lack of resources on the GPU or a true error in the call */
120   PETSC_ERR_MPI            = 98,  /* general MPI error */
121   PETSC_ERR_RETURN         = 99,  /* PetscError() incorrectly returned an error code of 0 */
122   PETSC_ERR_MEM_LEAK       = 100, /* memory alloc/free imbalance */
123   PETSC_ERR_PYTHON         = 101, /* Exception in Python */
124   PETSC_ERR_MAX_VALUE      = 102, /* this is always the one more than the largest error code */
125 
126   /*
127     do not use, exist purely to make the enum bounds equal that of a regular int (so conversion
128     to int in main() is not undefined behavior)
129   */
130   PETSC_ERR_MIN_SIGNED_BOUND_DO_NOT_USE = INT_MIN,
131   PETSC_ERR_MAX_SIGNED_BOUND_DO_NOT_USE = INT_MAX
132 } PETSC_ERROR_CODE_ENUM_NAME;
133 
134 #ifndef PETSC_USE_STRICT_PETSCERRORCODE
135 typedef int PetscErrorCode;
136 
137   /*
138   Needed so that C++ lambdas can deduce the return type as PetscErrorCode from
139   PetscFunctionReturn(PETSC_SUCCESS). Otherwise we get
140 
141   error: return type '(unnamed enum at include/petscsystypes.h:50:1)' must match previous
142   return type 'int' when lambda expression has unspecified explicit return type
143   PetscFunctionReturn(PETSC_SUCCESS);
144   ^
145 */
146   #define PETSC_SUCCESS ((PetscErrorCode)0)
147 #endif
148 
149 #undef PETSC_ERROR_CODE_NODISCARD
150 #undef PETSC_ERROR_CODE_TYPEDEF
151 #undef PETSC_ERROR_CODE_ENUM_NAME
152 
153 /*MC
154     PetscClassId - A unique id used to identify each PETSc class.
155 
156     Level: developer
157 
158     Note:
159     Use `PetscClassIdRegister()` to obtain a new value for a new class being created. Usually
160     XXXInitializePackage() calls it for each class it defines.
161 
162     Developer Note:
163     Internal integer stored in the `_p_PetscObject` data structure. These are all computed by an offset from the lowest one, `PETSC_SMALLEST_CLASSID`.
164 
165 .seealso: `PetscClassIdRegister()`, `PetscLogEventRegister()`, `PetscHeaderCreate()`
166 M*/
167 typedef int PetscClassId;
168 
169 /*MC
170     PetscMPIInt - datatype used to represent 'int' parameters to MPI functions.
171 
172     Level: intermediate
173 
174     Notes:
175     This is always a 32-bit integer, sometimes it is the same as `PetscInt`, but if PETSc was built with `--with-64-bit-indices` but
176     standard C/Fortran integers are 32-bit then this is NOT the same as `PetscInt`; it remains 32-bit.
177 
178     `PetscMPIIntCast`(a,&b) checks if the given `PetscInt` a will fit in a `PetscMPIInt`, if not it
179     generates a `PETSC_ERR_ARG_OUTOFRANGE` error.
180 
181 .seealso: [](stylePetscCount), `PetscBLASInt`, `PetscInt`, `PetscMPIIntCast()`
182 M*/
183 typedef int PetscMPIInt;
184 
185 /* Limit MPI to 32-bits */
186 enum {
187   PETSC_MPI_INT_MIN = INT_MIN,
188   PETSC_MPI_INT_MAX = INT_MAX
189 };
190 
191 /*MC
192     PetscSizeT - datatype used to represent sizes in memory (like `size_t`)
193 
194     Level: intermediate
195 
196     Notes:
197     This is equivalent to `size_t`, but defined for consistency with Fortran, which lacks a native equivalent of `size_t`.
198 
199 .seealso: `PetscInt`, `PetscInt64`, `PetscCount`
200 M*/
201 typedef size_t PetscSizeT;
202 
203 /*MC
204     PetscCount - signed datatype used to represent counts
205 
206     Level: intermediate
207 
208     Notes:
209     This is equivalent to `ptrdiff_t`, but defined for consistency with Fortran, which lacks a native equivalent of `ptrdiff_t`.
210 
211     Use `PetscCount_FMT` to format with `PetscPrintf()`, `printf()`, and related functions.
212 
213 .seealso: [](stylePetscCount), `PetscInt`, `PetscInt64`, `PetscSizeT`
214 M*/
215 typedef ptrdiff_t PetscCount;
216 #define PetscCount_FMT "td"
217 
218 /*MC
219     PetscEnum - datatype used to pass enum types within PETSc functions.
220 
221     Level: intermediate
222 
223 .seealso: `PetscOptionsGetEnum()`, `PetscOptionsEnum()`, `PetscBagRegisterEnum()`
224 M*/
225 typedef enum {
226   ENUM_DUMMY
227 } PetscEnum;
228 
229 typedef short PetscShort;
230 typedef float PetscFloat;
231 
232 /*MC
233   PetscInt - PETSc type that represents an integer, used primarily to
234              represent size of arrays and indexing into arrays. Its size can be configured with the option `--with-64-bit-indices` to be either 32-bit (default) or 64-bit.
235 
236   Level: beginner
237 
238   Notes:
239   For MPI calls that require datatypes, use `MPIU_INT` as the datatype for `PetscInt`. It will automatically work correctly regardless of the size of `PetscInt`.
240 
241 .seealso: `PetscBLASInt`, `PetscMPIInt`, `PetscReal`, `PetscScalar`, `PetscComplex`, `PetscInt`, `MPIU_REAL`, `MPIU_SCALAR`, `MPIU_COMPLEX`, `MPIU_INT`, `PetscIntCast()`
242 M*/
243 
244 #if defined(PETSC_HAVE_STDINT_H)
245   #include <stdint.h>
246 #endif
247 #if defined(PETSC_HAVE_INTTYPES_H)
248   #if !defined(__STDC_FORMAT_MACROS)
249     #define __STDC_FORMAT_MACROS /* required for using PRId64 from c++ */
250   #endif
251   #include <inttypes.h>
252   #if !defined(PRId64)
253     #define PRId64 "ld"
254   #endif
255 #endif
256 
257 #if defined(PETSC_HAVE_STDINT_H) && defined(PETSC_HAVE_INTTYPES_H) && (defined(PETSC_HAVE_MPIUNI) || defined(PETSC_HAVE_MPI_INT64_T)) /* MPI_INT64_T is not guaranteed to be a macro */
258 typedef int64_t PetscInt64;
259 
260   #define PETSC_INT64_MIN INT64_MIN
261   #define PETSC_INT64_MAX INT64_MAX
262 
263 #elif (PETSC_SIZEOF_LONG_LONG == 8)
264 typedef long long PetscInt64;
265 
266   #define PETSC_INT64_MIN LLONG_MIN
267   #define PETSC_INT64_MAX LLONG_MAX
268 
269 #elif defined(PETSC_HAVE___INT64)
270 typedef __int64 PetscInt64;
271 
272   #define PETSC_INT64_MIN INT64_MIN
273   #define PETSC_INT64_MAX INT64_MAX
274 
275 #else
276   #error "cannot determine PetscInt64 type"
277 #endif
278 
279 #if PETSC_SIZEOF_SIZE_T == 4
280   #define PETSC_COUNT_MIN INT_MIN
281   #define PETSC_COUNT_MAX INT_MAX
282 #else
283   #define PETSC_COUNT_MIN PETSC_INT64_MIN
284   #define PETSC_COUNT_MAX PETSC_INT64_MAX
285 #endif
286 
287 typedef int32_t PetscInt32;
288 #define PETSC_INT32_MIN INT32_MIN
289 #define PETSC_INT32_MAX INT32_MAX
290 
291 #if defined(PETSC_USE_64BIT_INDICES)
292 typedef PetscInt64 PetscInt;
293 
294   #define PETSC_INT_MIN PETSC_INT64_MIN
295   #define PETSC_INT_MAX PETSC_INT64_MAX
296   #define PetscInt_FMT  PetscInt64_FMT
297 #else
298 typedef int PetscInt;
299 
300 enum {
301   PETSC_INT_MIN = INT_MIN,
302   PETSC_INT_MAX = INT_MAX
303 };
304   #define PetscInt_FMT "d"
305 #endif
306 
307 #define PETSC_UINT16_MAX 65535
308 
309 /* deprecated */
310 #define PETSC_MIN_INT    PETSC_INT_MIN
311 #define PETSC_MAX_INT    PETSC_INT_MAX
312 #define PETSC_MAX_UINT16 PETSC_UINT16_MAX
313 
314 #if defined(PETSC_HAVE_STDINT_H) && defined(PETSC_HAVE_INTTYPES_H) && (defined(PETSC_HAVE_MPIUNI) || defined(PETSC_HAVE_MPI_INT64_T)) /* MPI_INT64_T is not guaranteed to be a macro */
315   #define MPIU_INT64     MPI_INT64_T
316   #define PetscInt64_FMT PRId64
317 #elif (PETSC_SIZEOF_LONG_LONG == 8)
318   #define MPIU_INT64     MPI_LONG_LONG_INT
319   #define PetscInt64_FMT "lld"
320 #elif defined(PETSC_HAVE___INT64)
321   #define MPIU_INT64     MPI_INT64_T
322   #define PetscInt64_FMT "ld"
323 #else
324   #error "cannot determine PetscInt64 type"
325 #endif
326 
327 #define MPIU_INT32     MPI_INT32_T
328 #define PetscInt32_FMT PRId32
329 
330 /*MC
331    PetscBLASInt - datatype used to represent 'int' parameters to BLAS/LAPACK functions.
332 
333    Level: intermediate
334 
335    Notes:
336    Usually this is the same as `PetscInt`, but if PETSc was built with `--with-64-bit-indices` but
337    standard C/Fortran integers are 32-bit then this may not be the same as `PetscInt`,
338    except on some BLAS/LAPACK implementations that support 64-bit integers see the notes below.
339 
340    `PetscErrorCode` `PetscBLASIntCast`(a,&b) checks if the given `PetscInt` a will fit in a `PetscBLASInt`, if not it
341     generates a `PETSC_ERR_ARG_OUTOFRANGE` error
342 
343    Installation Notes\:
344    ./configure automatically determines the size of the integers used by BLAS/LAPACK except when `--with-batch` is used
345    in that situation one must know (by some other means) if the integers used by BLAS/LAPACK are 64-bit and if so pass the flag `--known-64-bit-blas-indices`
346 
347    MATLAB ships with BLAS and LAPACK that use 64-bit integers, for example if you run ./configure with, the option
348     `--with-blaslapack-lib`=[/Applications/MATLAB_R2010b.app/bin/maci64/libmwblas.dylib,/Applications/MATLAB_R2010b.app/bin/maci64/libmwlapack.dylib]
349 
350    MKL ships with both 32 and 64-bit integer versions of the BLAS and LAPACK. If you pass the flag `-with-64-bit-blas-indices` PETSc will link
351    against the 64-bit version, otherwise it uses the 32-bit version
352 
353    OpenBLAS can be built to use 64-bit integers. The ./configure options `--download-openblas` `-with-64-bit-blas-indices` will build a 64-bit integer version
354 
355    External packages such as hypre, ML, SuperLU etc do not provide any support for passing 64-bit integers to BLAS/LAPACK so cannot
356    be used with PETSc when PETSc links against 64-bit integer BLAS/LAPACK. ./configure will generate an error if you attempt to link PETSc against any of
357    these external libraries while using 64-bit integer BLAS/LAPACK.
358 
359 .seealso: `PetscMPIInt`, `PetscInt`, `PetscBLASIntCast()`
360 M*/
361 #if defined(PETSC_HAVE_64BIT_BLAS_INDICES)
362 typedef PetscInt64 PetscBLASInt;
363 
364   #define PETSC_BLAS_INT_MIN PETSC_INT64_MIN
365   #define PETSC_BLAS_INT_MAX PETSC_INT64_MAX
366   #define PetscBLASInt_FMT   PetscInt64_FMT
367 #else
368 typedef int PetscBLASInt;
369 
370 enum {
371   PETSC_BLAS_INT_MIN = INT_MIN,
372   PETSC_BLAS_INT_MAX = INT_MAX
373 };
374 
375   #define PetscBLASInt_FMT "d"
376 #endif
377 
378 /*MC
379    PetscCuBLASInt - datatype used to represent 'int' parameters to cuBLAS/cuSOLVER functions.
380 
381    Level: intermediate
382 
383    Notes:
384    As of this writing `PetscCuBLASInt` is always the system `int`.
385 
386   `PetscErrorCode` `PetscCuBLASIntCast`(a,&b) checks if the given `PetscInt` a will fit in a `PetscCuBLASInt`, if not it
387    generates a `PETSC_ERR_ARG_OUTOFRANGE` error
388 
389 .seealso: `PetscBLASInt`, `PetscMPIInt`, `PetscInt`, `PetscCuBLASIntCast()`
390 M*/
391 typedef int PetscCuBLASInt;
392 
393 enum {
394   PETSC_CUBLAS_INT_MIN = INT_MIN,
395   PETSC_CUBLAS_INT_MAX = INT_MAX
396 };
397 
398 /*MC
399    PetscHipBLASInt - datatype used to represent 'int' parameters to hipBLAS/hipSOLVER functions.
400 
401    Level: intermediate
402 
403    Notes:
404    `PetscHipBLASInt` is always the system `int`.
405 
406    `PetscErrorCode` `PetscHipBLASIntCast`(a,&b) checks if the given `PetscInt` a will fit in a `PetscHipBLASInt`, if not it
407    generates a `PETSC_ERR_ARG_OUTOFRANGE` error
408 
409 .seealso: `PetscBLASInt`, `PetscMPIInt`, `PetscInt`, `PetscHipBLASIntCast()`
410 M*/
411 typedef int PetscHipBLASInt;
412 
413 enum {
414   PETSC_HIPBLAS_INT_MIN = INT_MIN,
415   PETSC_HIPBLAS_INT_MAX = INT_MAX
416 };
417 
418 /*MC
419    PetscExodusIIInt - datatype used to represent 'int' parameters to ExodusII functions.
420 
421    Level: intermediate
422 
423    Notes:
424    This is the same as `int`
425 
426 .seealso: `PetscMPIInt`, `PetscInt`, `PetscExodusIIFloat`, `PetscBLASIntCast()`
427 M*/
428 typedef int PetscExodusIIInt;
429 #define PetscExodusIIInt_FMT "d"
430 
431 /*MC
432    PetscExodusIIFloat - datatype used to represent 'float' parameters to ExodusII functions.
433 
434    Level: intermediate
435 
436    Notes:
437    This is the same as `float`
438 
439 .seealso: `PetscMPIInt`, `PetscInt`, `PetscExodusIIInt`, `PetscBLASIntCast()`
440 M*/
441 typedef float PetscExodusIIFloat;
442 
443 /*E
444    PetscBool  - Logical variable.
445 
446    Level: beginner
447 
448    Notes:
449    This is a C bool.
450 
451    Use `MPI_C_BOOL` for communicating with MPI calls in C, C++, and Fortran.
452 
453    Fortran Note:
454    This is a `logical(C_BOOL)`.
455 
456    Developer Note:
457    We should deprecate this definition since there is a native representation in all the languages.
458 
459 .seealso: `PETSC_TRUE`, `PETSC_FALSE`, `PetscNot()`, `PetscBool3`
460 E*/
461 typedef bool PetscBool;
462 #define PETSC_FALSE false
463 #define PETSC_TRUE  true
464 PETSC_EXTERN const char *const PetscBools[];
465 
466 /*E
467    PetscBool3  - Ternary logical variable. Actually an enum in C and a 4 byte integer in Fortran.
468 
469    Level: beginner
470 
471    Note:
472    Should not be used with the if (flg) or if (!flg) syntax.
473 
474 .seealso: `PETSC_TRUE`, `PETSC_FALSE`, `PetscNot()`, `PETSC_BOOL3_TRUE`, `PETSC_BOOL3_FALSE`, `PETSC_BOOL3_UNKNOWN`
475 E*/
476 typedef enum {
477   PETSC_BOOL3_FALSE   = 0,
478   PETSC_BOOL3_TRUE    = 1,
479   PETSC_BOOL3_UNKNOWN = -1 /* the value is unknown at the time of query, but might be determined later */
480 } PetscBool3;
481 
482 #define PetscBool3ToBool(a) ((a) == PETSC_BOOL3_TRUE ? PETSC_TRUE : PETSC_FALSE)
483 #define PetscBoolToBool3(a) ((a) == PETSC_TRUE ? PETSC_BOOL3_TRUE : PETSC_BOOL3_FALSE)
484 
485 /*MC
486    PetscReal - PETSc type that represents a real number version of `PetscScalar`
487 
488    Level: beginner
489 
490    Notes:
491    For MPI calls that require datatypes, use `MPIU_REAL` as the datatype for `PetscReal` and `MPIU_SUM`, `MPIU_MAX`, etc. for operations.
492    They will automatically work correctly regardless of the size of `PetscReal`.
493 
494    See `PetscScalar` for details on how to ./configure the size of `PetscReal`.
495 
496 .seealso: `PetscScalar`, `PetscComplex`, `PetscInt`, `MPIU_REAL`, `MPIU_SCALAR`, `MPIU_COMPLEX`, `MPIU_INT`
497 M*/
498 
499 #if defined(PETSC_USE_REAL_SINGLE)
500 typedef float PetscReal;
501 #elif defined(PETSC_USE_REAL_DOUBLE)
502 typedef double PetscReal;
503 #elif defined(PETSC_USE_REAL___FLOAT128)
504   #if defined(__cplusplus)
505 extern "C" {
506   #endif
507   #include <quadmath.h>
508   #if defined(__cplusplus)
509 }
510   #endif
511 typedef __float128 PetscReal;
512 #elif defined(PETSC_USE_REAL___FP16)
513 typedef __fp16 PetscReal;
514 #endif /* PETSC_USE_REAL_* */
515 
516 /*MC
517    PetscComplex - PETSc type that represents a complex number with precision matching that of `PetscReal`.
518 
519    Synopsis:
520    #include <petscsys.h>
521    PetscComplex number = 1. + 2.*PETSC_i;
522 
523    Level: beginner
524 
525    Notes:
526    For MPI calls that require datatypes, use `MPIU_COMPLEX` as the datatype for `PetscComplex` and `MPIU_SUM` etc for operations.
527    They will automatically work correctly regardless of the size of `PetscComplex`.
528 
529    See `PetscScalar` for details on how to ./configure the size of `PetscReal`
530 
531    Complex numbers are automatically available if PETSc was able to find a working complex implementation
532 
533     PETSc has a 'fix' for complex numbers to support expressions such as `std::complex<PetscReal>` + `PetscInt`, which are not supported by the standard
534     C++ library, but are convenient for PETSc users. If the C++ compiler is able to compile code in `petsccxxcomplexfix.h` (This is checked by
535     configure), we include `petsccxxcomplexfix.h` to provide this convenience.
536 
537     If the fix causes conflicts, or one really does not want this fix for a particular C++ file, one can define `PETSC_SKIP_CXX_COMPLEX_FIX`
538     at the beginning of the C++ file to skip the fix.
539 
540 .seealso: `PetscReal`, `PetscScalar`, `PetscComplex`, `PetscInt`, `MPIU_REAL`, `MPIU_SCALAR`, `MPIU_COMPLEX`, `MPIU_INT`, `PETSC_i`
541 M*/
542 #if !defined(PETSC_SKIP_COMPLEX)
543   #if defined(PETSC_CLANGUAGE_CXX)
544     #if !defined(PETSC_USE_REAL___FP16) && !defined(PETSC_USE_REAL___FLOAT128)
545       #if defined(__cplusplus) && defined(PETSC_HAVE_CXX_COMPLEX) /* enable complex for library code */
546         #define PETSC_HAVE_COMPLEX 1
547       #elif !defined(__cplusplus) && defined(PETSC_HAVE_C99_COMPLEX) && defined(PETSC_HAVE_CXX_COMPLEX) /* User code only - conditional on library code complex support */
548         #define PETSC_HAVE_COMPLEX 1
549       #endif
550     #elif defined(PETSC_USE_REAL___FLOAT128) && defined(PETSC_HAVE_C99_COMPLEX)
551       #define PETSC_HAVE_COMPLEX 1
552     #endif
553   #else /* !PETSC_CLANGUAGE_CXX */
554     #if !defined(PETSC_USE_REAL___FP16)
555       #if !defined(__cplusplus) && defined(PETSC_HAVE_C99_COMPLEX) /* enable complex for library code */
556         #define PETSC_HAVE_COMPLEX 1
557       #elif defined(__cplusplus) && defined(PETSC_HAVE_C99_COMPLEX) && defined(PETSC_HAVE_CXX_COMPLEX) /* User code only - conditional on library code complex support */
558         #define PETSC_HAVE_COMPLEX 1
559       #endif
560     #endif
561   #endif /* PETSC_CLANGUAGE_CXX */
562 #endif   /* !PETSC_SKIP_COMPLEX */
563 
564 #if defined(PETSC_HAVE_COMPLEX)
565   #if defined(__cplusplus) /* C++ complex support */
566     /* Locate a C++ complex template library */
567     #if defined(PETSC_DESIRE_KOKKOS_COMPLEX) /* Defined in petscvec_kokkos.hpp for *.kokkos.cxx files */
568       #define petsccomplexlib Kokkos
569       #include <Kokkos_Complex.hpp>
570     #elif (defined(__CUDACC__) && defined(PETSC_HAVE_CUDA)) || (defined(__HIPCC__) && defined(PETSC_HAVE_HIP))
571       #define petsccomplexlib thrust
572       #include <thrust/complex.h>
573     #elif defined(PETSC_USE_REAL___FLOAT128)
574       #include <complex.h>
575     #else
576       #define petsccomplexlib std
577       #include <complex>
578     #endif
579 
580     /* Define PetscComplex based on the precision */
581     #if defined(PETSC_USE_REAL_SINGLE)
582 typedef petsccomplexlib::complex<float> PetscComplex;
583     #elif defined(PETSC_USE_REAL_DOUBLE)
584 typedef petsccomplexlib::complex<double> PetscComplex;
585     #elif defined(PETSC_USE_REAL___FLOAT128)
586 typedef __complex128 PetscComplex;
587     #endif
588 
589     /* Include a PETSc C++ complex 'fix'. Check PetscComplex manual page for details */
590     #if defined(PETSC_HAVE_CXX_COMPLEX_FIX) && !defined(PETSC_SKIP_CXX_COMPLEX_FIX)
591       #include <petsccxxcomplexfix.h>
592     #endif
593   #else /* c99 complex support */
594     #include <complex.h>
595     #if defined(PETSC_USE_REAL_SINGLE) || defined(PETSC_USE_REAL___FP16)
596 typedef float _Complex PetscComplex;
597     #elif defined(PETSC_USE_REAL_DOUBLE)
598 typedef double _Complex PetscComplex;
599     #elif defined(PETSC_USE_REAL___FLOAT128)
600 typedef __complex128 PetscComplex;
601     #endif /* PETSC_USE_REAL_* */
602   #endif   /* !__cplusplus */
603 #endif     /* PETSC_HAVE_COMPLEX */
604 
605 /*MC
606    PetscScalar - PETSc type that represents either a double precision real number, a double precision
607                  complex number, a single precision real number, a __float128 real or complex or a __fp16 real - if the code is configured
608                  with `--with-scalar-type`=real,complex `--with-precision`=single,double,__float128,__fp16
609 
610    Level: beginner
611 
612    Note:
613    For MPI calls that require datatypes, use `MPIU_SCALAR` as the datatype for `PetscScalar` and `MPIU_SUM`, etc for operations. They will automatically work correctly regardless of the size of `PetscScalar`.
614 
615 .seealso: `PetscReal`, `PetscComplex`, `PetscInt`, `MPIU_REAL`, `MPIU_SCALAR`, `MPIU_COMPLEX`, `MPIU_INT`, `PetscRealPart()`, `PetscImaginaryPart()`
616 M*/
617 
618 #if defined(PETSC_USE_COMPLEX) && defined(PETSC_HAVE_COMPLEX)
619 typedef PetscComplex PetscScalar;
620 #else  /* PETSC_USE_COMPLEX */
621 typedef PetscReal PetscScalar;
622 #endif /* PETSC_USE_COMPLEX */
623 
624 /*E
625     PetscCopyMode  - Determines how an array or `PetscObject` passed to certain functions is copied or retained by the aggregate `PetscObject`
626 
627    Values for array input:
628 +   `PETSC_COPY_VALUES` - the array values are copied into new space, the user is free to reuse or delete the passed in array
629 .   `PETSC_OWN_POINTER` - the array values are NOT copied, the object takes ownership of the array and will free it later, the user cannot change or
630                           delete the array. The array MUST have been obtained with `PetscMalloc()`. Hence this mode cannot be used in Fortran.
631 -   `PETSC_USE_POINTER` - the array values are NOT copied, the object uses the array but does NOT take ownership of the array. The user cannot use
632                           the array but the user must delete the array after the object is destroyed.
633 
634    Values for PetscObject:
635 +   `PETSC_COPY_VALUES` - the input `PetscObject` is cloned into the aggregate `PetscObject`; the user is free to reuse/modify the input `PetscObject` without side effects.
636 .   `PETSC_OWN_POINTER` - the input `PetscObject` is referenced by pointer (with reference count), thus should not be modified by the user.
637                           increases its reference count).
638 -   `PETSC_USE_POINTER` - invalid for `PetscObject` inputs.
639 
640    Level: beginner
641 
642 .seealso: `PetscInsertMode`
643 E*/
644 typedef enum {
645   PETSC_COPY_VALUES,
646   PETSC_OWN_POINTER,
647   PETSC_USE_POINTER
648 } PetscCopyMode;
649 PETSC_EXTERN const char *const PetscCopyModes[];
650 
651 /*MC
652     PETSC_FALSE - False value of `PetscBool`
653 
654     Level: beginner
655 
656     Note:
657     Zero integer
658 
659 .seealso: `PetscBool`, `PetscBool3`, `PETSC_TRUE`
660 M*/
661 
662 /*MC
663     PETSC_TRUE - True value of `PetscBool`
664 
665     Level: beginner
666 
667     Note:
668     Nonzero integer
669 
670 .seealso: `PetscBool`, `PetscBool3`, `PETSC_FALSE`
671 M*/
672 
673 /*MC
674     PetscLogDouble - Used for logging times
675 
676   Level: developer
677 
678   Note:
679   Contains double precision numbers that are not used in the numerical computations, but rather in logging, timing etc.
680 
681 .seealso: `PetscBool`, `PetscDataType`
682 M*/
683 typedef double PetscLogDouble;
684 
685 /*E
686     PetscDataType - Used for handling different basic data types.
687 
688    Level: beginner
689 
690    Notes:
691    Use of this should be avoided if one can directly use `MPI_Datatype` instead.
692 
693    `PETSC_INT` is the datatype for a `PetscInt`, regardless of whether it is 4 or 8 bytes.
694    `PETSC_REAL`, `PETSC_COMPLEX` and `PETSC_SCALAR` are the datatypes for `PetscReal`, `PetscComplex` and `PetscScalar`, regardless of their sizes.
695 
696    Developer Notes:
697    It would be nice if we could always just use MPI Datatypes, why can we not?
698 
699    If you change any values in `PetscDatatype` make sure you update their usage in
700    share/petsc/matlab/PetscBagRead.m and share/petsc/matlab/@PetscOpenSocket/read/write.m
701 
702    TODO:
703    Remove use of improper `PETSC_ENUM`
704 
705 .seealso: `PetscBinaryRead()`, `PetscBinaryWrite()`, `PetscDataTypeToMPIDataType()`,
706           `PetscDataTypeGetSize()`
707 E*/
708 typedef enum {
709   PETSC_DATATYPE_UNKNOWN = 0,
710   PETSC_DOUBLE           = 1,
711   PETSC_COMPLEX          = 2,
712   PETSC_LONG             = 3,
713   PETSC_SHORT            = 4,
714   PETSC_FLOAT            = 5,
715   PETSC_CHAR             = 6,
716   PETSC_BIT_LOGICAL      = 7,
717   PETSC_ENUM             = 8,
718   PETSC_BOOL             = 9,
719   PETSC___FLOAT128       = 10,
720   PETSC_OBJECT           = 11,
721   PETSC_FUNCTION         = 12,
722   PETSC_STRING           = 13,
723   PETSC___FP16           = 14,
724   PETSC_STRUCT           = 15,
725   PETSC_INT              = 16,
726   PETSC_INT64            = 17,
727   PETSC_COUNT            = 18,
728   PETSC_INT32            = 19,
729 } PetscDataType;
730 PETSC_EXTERN const char *const PetscDataTypes[];
731 
732 #if defined(PETSC_USE_REAL_SINGLE)
733   #define PETSC_REAL PETSC_FLOAT
734 #elif defined(PETSC_USE_REAL_DOUBLE)
735   #define PETSC_REAL PETSC_DOUBLE
736 #elif defined(PETSC_USE_REAL___FLOAT128)
737   #define PETSC_REAL PETSC___FLOAT128
738 #elif defined(PETSC_USE_REAL___FP16)
739   #define PETSC_REAL PETSC___FP16
740 #else
741   #define PETSC_REAL PETSC_DOUBLE
742 #endif
743 
744 #if defined(PETSC_USE_COMPLEX)
745   #define PETSC_SCALAR PETSC_COMPLEX
746 #else
747   #define PETSC_SCALAR PETSC_REAL
748 #endif
749 
750 #define PETSC_FORTRANADDR PETSC_LONG
751 
752 /*S
753   PetscToken - 'Token' used for managing tokenizing strings
754 
755   Level: intermediate
756 
757 .seealso: `PetscTokenCreate()`, `PetscTokenFind()`, `PetscTokenDestroy()`
758 S*/
759 typedef struct _n_PetscToken *PetscToken;
760 
761 /*S
762    PetscObject - any PETSc object, for example: `PetscViewer`, `Mat`, `Vec`, `KSP`, `DM`
763 
764    Level: beginner
765 
766    Notes:
767    This is the base class from which all PETSc objects are derived.
768 
769    In certain situations one can cast an object, for example a `Vec`, to a `PetscObject` with (`PetscObject`)vec
770 
771 .seealso: `PetscObjectDestroy()`, `PetscObjectView()`, `PetscObjectGetName()`, `PetscObjectSetName()`, `PetscObjectReference()`, `PetscObjectDereference()`
772 S*/
773 typedef struct _p_PetscObject *PetscObject;
774 
775 /*MC
776     PetscObjectId - unique integer Id for a `PetscObject`
777 
778     Level: developer
779 
780     Note:
781     Unlike pointer values, object ids are never reused so one may save a `PetscObjectId` and compare it to one obtained later from a `PetscObject` to determine
782     if the objects are the same. Never compare two object pointer values.
783 
784 .seealso: `PetscObjectState`, `PetscObjectGetId()`
785 M*/
786 typedef PetscInt64 PetscObjectId;
787 
788 /*MC
789     PetscObjectState - integer state for a `PetscObject`
790 
791     Level: developer
792 
793     Note:
794     Object state is always-increasing and (for objects that track state) can be used to determine if an object has
795     changed since the last time you interacted with it.  It is 64-bit so that it will not overflow for a very long time.
796 
797 .seealso: `PetscObjectId`, `PetscObjectStateGet()`, `PetscObjectStateIncrease()`, `PetscObjectStateSet()`
798 M*/
799 typedef PetscInt64 PetscObjectState;
800 
801 /*S
802      PetscFunctionList - Linked list of functions, possibly stored in dynamic libraries, accessed
803       by string name
804 
805    Level: advanced
806 
807 .seealso: `PetscFunctionListAdd()`, `PetscFunctionListDestroy()`
808 S*/
809 typedef struct _n_PetscFunctionList *PetscFunctionList;
810 
811 /*E
812   PetscFileMode - Access mode for a file.
813 
814   Values:
815 +  `FILE_MODE_UNDEFINED`     - initial invalid value
816 .  `FILE_MODE_READ`          - open a file at its beginning for reading
817 .  `FILE_MODE_WRITE`         - open a file at its beginning for writing (will create if the file does not exist)
818 .  `FILE_MODE_APPEND`        - open a file at end for writing
819 .  `FILE_MODE_UPDATE`        - open a file for updating, meaning for reading and writing
820 -  `FILE_MODE_APPEND_UPDATE` - open a file for updating, meaning for reading and writing, at the end
821 
822   Level: beginner
823 
824 .seealso: `PetscViewerFileSetMode()`
825 E*/
826 typedef enum {
827   FILE_MODE_UNDEFINED     = -1,
828   FILE_MODE_READ          = 0,
829   FILE_MODE_WRITE         = 1,
830   FILE_MODE_APPEND        = 2,
831   FILE_MODE_UPDATE        = 3,
832   FILE_MODE_APPEND_UPDATE = 4
833 } PetscFileMode;
834 PETSC_EXTERN const char *const PetscFileModes[];
835 
836 typedef void *PetscDLHandle;
837 typedef enum {
838   PETSC_DL_DECIDE = 0,
839   PETSC_DL_NOW    = 1,
840   PETSC_DL_LOCAL  = 2
841 } PetscDLMode;
842 
843 /*S
844    PetscObjectList - Linked list of PETSc objects, each accessible by string name
845 
846    Level: developer
847 
848    Note:
849    Used by `PetscObjectCompose()` and `PetscObjectQuery()`
850 
851 .seealso: `PetscObjectListAdd()`, `PetscObjectListDestroy()`, `PetscObjectListFind()`, `PetscObjectCompose()`, `PetscObjectQuery()`, `PetscFunctionList`
852 S*/
853 typedef struct _n_PetscObjectList *PetscObjectList;
854 
855 /*S
856    PetscDLLibrary - Linked list of dynamic libraries to search for functions
857 
858    Level: developer
859 
860 .seealso: `PetscDLLibraryOpen()`
861 S*/
862 typedef struct _n_PetscDLLibrary *PetscDLLibrary;
863 
864 /*S
865    PetscContainer - Simple PETSc object that contains a pointer to any required data
866 
867    Level: advanced
868 
869    Note:
870    This is useful to attach arbitrary data to a `PetscObject` with `PetscObjectCompose()` and `PetscObjectQuery()`
871 
872 .seealso: `PetscObject`, `PetscContainerCreate()`, `PetscObjectCompose()`, `PetscObjectQuery()`
873 S*/
874 typedef struct _p_PetscContainer *PetscContainer;
875 
876 /*S
877    PetscRandom - Abstract PETSc object that manages generating random numbers
878 
879    Level: intermediate
880 
881 .seealso: `PetscRandomCreate()`, `PetscRandomGetValue()`, `PetscRandomType`
882 S*/
883 typedef struct _p_PetscRandom *PetscRandom;
884 
885 /*
886    In binary files variables are stored using the following lengths,
887   regardless of how they are stored in memory on any one particular
888   machine. Use these rather than sizeof() in computing sizes for
889   PetscBinarySeek().
890 */
891 #define PETSC_BINARY_INT_SIZE    (32 / 8)
892 #define PETSC_BINARY_FLOAT_SIZE  (32 / 8)
893 #define PETSC_BINARY_CHAR_SIZE   (8 / 8)
894 #define PETSC_BINARY_SHORT_SIZE  (16 / 8)
895 #define PETSC_BINARY_DOUBLE_SIZE (64 / 8)
896 #define PETSC_BINARY_SCALAR_SIZE sizeof(PetscScalar)
897 
898 /*E
899   PetscBinarySeekType - argument to `PetscBinarySeek()`
900 
901   Values:
902 +  `PETSC_BINARY_SEEK_SET` - offset is an absolute location in the file
903 .  `PETSC_BINARY_SEEK_CUR` - offset is an offset from the current location of the file pointer
904 -  `PETSC_BINARY_SEEK_END` - offset is an offset from the end of the file
905 
906   Level: advanced
907 
908 .seealso: `PetscBinarySeek()`, `PetscBinarySynchronizedSeek()`
909 E*/
910 typedef enum {
911   PETSC_BINARY_SEEK_SET = 0,
912   PETSC_BINARY_SEEK_CUR = 1,
913   PETSC_BINARY_SEEK_END = 2
914 } PetscBinarySeekType;
915 
916 /*E
917    PetscBuildTwoSidedType - algorithm for setting up two-sided communication for use with `PetscSF`
918 
919    Values:
920 +  `PETSC_BUILDTWOSIDED_ALLREDUCE`  - classical algorithm using an `MPI_Allreduce()` with
921                                       a buffer of length equal to the communicator size. Not memory-scalable due to
922                                       the large reduction size. Requires only an MPI-1 implementation.
923 .  `PETSC_BUILDTWOSIDED_IBARRIER`   - nonblocking algorithm based on `MPI_Issend()` and `MPI_Ibarrier()`.
924                                       Proved communication-optimal in Hoefler, Siebert, and Lumsdaine (2010). Requires an MPI-3 implementation.
925 -  `PETSC_BUILDTWOSIDED_REDSCATTER` - similar to above, but use more optimized function
926                                       that only communicates the part of the reduction that is necessary.  Requires an MPI-2 implementation.
927 
928    Level: developer
929 
930 .seealso: `PetscCommBuildTwoSided()`, `PetscCommBuildTwoSidedSetType()`, `PetscCommBuildTwoSidedGetType()`
931 E*/
932 typedef enum {
933   PETSC_BUILDTWOSIDED_NOTSET     = -1,
934   PETSC_BUILDTWOSIDED_ALLREDUCE  = 0,
935   PETSC_BUILDTWOSIDED_IBARRIER   = 1,
936   PETSC_BUILDTWOSIDED_REDSCATTER = 2
937   /* Updates here must be accompanied by updates in finclude/petscsys.h and the string array in mpits.c */
938 } PetscBuildTwoSidedType;
939 PETSC_EXTERN const char *const PetscBuildTwoSidedTypes[];
940 
941 /*E
942   InsertMode - How the entries are combined with the current values in the vectors or matrices
943 
944   Values:
945 +  `NOT_SET_VALUES`    - do not actually use the values
946 .  `INSERT_VALUES`     - replace the current values with the provided values, unless the index is marked as constrained by the `PetscSection`
947 .  `ADD_VALUES`        - add the values to the current values, unless the index is marked as constrained by the `PetscSection`
948 .  `MAX_VALUES`        - use the maximum of each current value and provided value
949 .  `MIN_VALUES`        - use the minimum of each current value and provided value
950 .  `INSERT_ALL_VALUES` - insert, even if indices that are not marked as constrained by the `PetscSection`
951 .  `ADD_ALL_VALUES`    - add, even if indices that are not marked as constrained by the `PetscSection`
952 .  `INSERT_BC_VALUES`  - insert, but ignore indices that are not marked as constrained by the `PetscSection`
953 -  `ADD_BC_VALUES`     - add, but ignore indices that are not marked as constrained by the `PetscSection`
954 
955   Level: beginner
956 
957   Note:
958   The `PetscSection` that determines the effects of the `InsertMode` values can be obtained by the `Vec` object with `VecGetDM()`
959   and `DMGetLocalSection()`.
960 
961   Not all options are supported for all operations or PETSc object types.
962 
963 .seealso: `VecSetValues()`, `MatSetValues()`, `VecSetValue()`, `VecSetValuesBlocked()`,
964           `VecSetValuesLocal()`, `VecSetValuesBlockedLocal()`, `MatSetValuesBlocked()`,
965           `MatSetValuesBlockedLocal()`, `MatSetValuesLocal()`, `VecScatterBegin()`, `VecScatterEnd()`
966 E*/
967 typedef enum {
968   NOT_SET_VALUES,
969   INSERT_VALUES,
970   ADD_VALUES,
971   MAX_VALUES,
972   MIN_VALUES,
973   INSERT_ALL_VALUES,
974   ADD_ALL_VALUES,
975   INSERT_BC_VALUES,
976   ADD_BC_VALUES
977 } InsertMode;
978 
979 /*MC
980     INSERT_VALUES - Put a value into a vector or matrix, overwrites any previous value
981 
982     Level: beginner
983 
984 .seealso: `InsertMode`, `VecSetValues()`, `MatSetValues()`, `VecSetValue()`, `VecSetValuesBlocked()`,
985           `VecSetValuesLocal()`, `VecSetValuesBlockedLocal()`, `MatSetValuesBlocked()`, `ADD_VALUES`,
986           `MatSetValuesBlockedLocal()`, `MatSetValuesLocal()`, `VecScatterBegin()`, `VecScatterEnd()`, `MAX_VALUES`
987 M*/
988 
989 /*MC
990     ADD_VALUES - Adds a value into a vector or matrix, if there previously was no value, just puts the
991                  value into that location
992 
993     Level: beginner
994 
995 .seealso: `InsertMode`, `VecSetValues()`, `MatSetValues()`, `VecSetValue()`, `VecSetValuesBlocked()`,
996           `VecSetValuesLocal()`, `VecSetValuesBlockedLocal()`, `MatSetValuesBlocked()`, `INSERT_VALUES`,
997           `MatSetValuesBlockedLocal()`, `MatSetValuesLocal()`, `VecScatterBegin()`, `VecScatterEnd()`, `MAX_VALUES`
998 M*/
999 
1000 /*MC
1001     MAX_VALUES - Puts the maximum of the scattered/gathered value and the current value into each location
1002 
1003     Level: beginner
1004 
1005 .seealso: `InsertMode`, `VecScatterBegin()`, `VecScatterEnd()`, `ADD_VALUES`, `INSERT_VALUES`
1006 M*/
1007 
1008 /*MC
1009     MIN_VALUES - Puts the minimal of the scattered/gathered value and the current value into each location
1010 
1011     Level: beginner
1012 
1013 .seealso: `InsertMode`, `VecScatterBegin()`, `VecScatterEnd()`, `ADD_VALUES`, `INSERT_VALUES`
1014 M*/
1015 
1016 /*S
1017    PetscSubcomm - A decomposition of an MPI communicator into subcommunicators
1018 
1019    Values:
1020 +   `PETSC_SUBCOMM_GENERAL`    - similar to `MPI_Comm_split()` each process sets the new communicator (color) they will belong to and the order within that communicator
1021 .   `PETSC_SUBCOMM_CONTIGUOUS` - each new communicator contains a set of process with contiguous ranks in the original MPI communicator
1022 -   `PETSC_SUBCOMM_INTERLACED` - each new communictor contains a set of processes equally far apart in rank from the others in that new communicator
1023 
1024    Sample Usage:
1025 .vb
1026        PetscSubcommCreate()
1027        PetscSubcommSetNumber()
1028        PetscSubcommSetType(PETSC_SUBCOMM_INTERLACED);
1029        ccomm = PetscSubcommChild()
1030        PetscSubcommDestroy()
1031 .ve
1032 
1033    Example:
1034    Consider a communicator with six processes split into 3 subcommunicators.
1035 .vb
1036    PETSC_SUBCOMM_CONTIGUOUS - the first communicator contains rank 0,1  the second rank 2,3 and the third rank 4,5 in the original ordering of the original communicator
1037    PETSC_SUBCOMM_INTERLACED - the first communicator contains rank 0,3, the second 1,4 and the third 2,5
1038 .ve
1039 
1040    Level: advanced
1041 
1042    Note:
1043    After a call to `PetscSubcommSetType()`, `PetscSubcommSetTypeGeneral()`, or `PetscSubcommSetFromOptions()` one may call
1044 .vb
1045      PetscSubcommChild() returns the associated subcommunicator on this process
1046      PetscSubcommContiguousParent() returns a parent communitor but with all child of the same subcommunicator having contiguous rank
1047 .ve
1048 
1049    Developer Note:
1050    This is used in objects such as `PCREDUNDANT` to manage the subcommunicators on which the redundant computations
1051    are performed.
1052 
1053 .seealso: `PetscSubcommCreate()`, `PetscSubcommSetNumber()`, `PetscSubcommSetType()`, `PetscSubcommView()`, `PetscSubcommSetFromOptions()`
1054 S*/
1055 typedef struct _n_PetscSubcomm *PetscSubcomm;
1056 typedef enum {
1057   PETSC_SUBCOMM_GENERAL    = 0,
1058   PETSC_SUBCOMM_CONTIGUOUS = 1,
1059   PETSC_SUBCOMM_INTERLACED = 2
1060 } PetscSubcommType;
1061 PETSC_EXTERN const char *const PetscSubcommTypes[];
1062 
1063 /*S
1064    PetscHeap - A simple class for managing heaps
1065 
1066    Level: intermediate
1067 
1068 .seealso: `PetscHeapCreate()`, `PetscHeapAdd()`, `PetscHeapPop()`, `PetscHeapPeek()`, `PetscHeapStash()`, `PetscHeapUnstash()`, `PetscHeapView()`, `PetscHeapDestroy()`
1069 S*/
1070 typedef struct _n_PetscHeap *PetscHeap;
1071 
1072 typedef struct _n_PetscShmComm *PetscShmComm;
1073 typedef struct _n_PetscOmpCtrl *PetscOmpCtrl;
1074 
1075 /*S
1076    PetscSegBuffer - a segmented extendable buffer
1077 
1078    Level: developer
1079 
1080 .seealso: `PetscSegBufferCreate()`, `PetscSegBufferGet()`, `PetscSegBufferExtract()`, `PetscSegBufferDestroy()`
1081 S*/
1082 typedef struct _n_PetscSegBuffer *PetscSegBuffer;
1083 
1084 typedef struct _n_PetscOptionsHelpPrinted *PetscOptionsHelpPrinted;
1085 
1086 /*S
1087      PetscBT - PETSc bitarrays, efficient storage of arrays of boolean values
1088 
1089      Level: advanced
1090 
1091      Notes:
1092      The following routines do not have their own manual pages
1093 
1094 .vb
1095      PetscBTCreate(m,&bt)         - creates a bit array with enough room to hold m values
1096      PetscBTDestroy(&bt)          - destroys the bit array
1097      PetscBTMemzero(m,bt)         - zeros the entire bit array (sets all values to false)
1098      PetscBTSet(bt,index)         - sets a particular entry as true
1099      PetscBTClear(bt,index)       - sets a particular entry as false
1100      PetscBTLookup(bt,index)      - returns the value
1101      PetscBTLookupSet(bt,index)   - returns the value and then sets it true
1102      PetscBTLookupClear(bt,index) - returns the value and then sets it false
1103      PetscBTLength(m)             - returns number of bytes in array with m bits
1104      PetscBTView(m,bt,viewer)     - prints all the entries in a bit array
1105 .ve
1106 
1107     PETSc does not check error flags on `PetscBTLookup()`, `PetscBTLookupSet()`, `PetscBTLength()` because error checking
1108     would cost hundreds more cycles then the operation.
1109 
1110 S*/
1111 typedef char *PetscBT;
1112 
1113 /* The number of bits in a byte */
1114 #define PETSC_BITS_PER_BYTE CHAR_BIT
1115