1 2 /* 3 This file contains routines for interfacing to random number generators. 4 This provides more than just an interface to some system random number 5 generator: 6 7 Numbers can be shuffled for use as random tuples 8 9 Multiple random number generators may be used 10 11 We are still not sure what interface we want here. There should be 12 one to reinitialize and set the seed. 13 */ 14 15 #include <../src/sys/classes/random/randomimpl.h> /*I "petscsys.h" I*/ 16 #include <petscviewer.h> 17 18 /* Logging support */ 19 PetscClassId PETSC_RANDOM_CLASSID; 20 21 #undef __FUNCT__ 22 #define __FUNCT__ "PetscRandomDestroy" 23 /*@ 24 PetscRandomDestroy - Destroys a context that has been formed by 25 PetscRandomCreate(). 26 27 Collective on PetscRandom 28 29 Intput Parameter: 30 . r - the random number generator context 31 32 Level: intermediate 33 34 .seealso: PetscRandomGetValue(), PetscRandomCreate(), VecSetRandom() 35 @*/ 36 PetscErrorCode PetscRandomDestroy(PetscRandom *r) 37 { 38 PetscErrorCode ierr; 39 40 PetscFunctionBegin; 41 if (!*r) PetscFunctionReturn(0); 42 PetscValidHeaderSpecific(*r,PETSC_RANDOM_CLASSID,1); 43 if (--((PetscObject)(*r))->refct > 0) {*r = 0; PetscFunctionReturn(0);} 44 ierr = PetscHeaderDestroy(r);CHKERRQ(ierr); 45 PetscFunctionReturn(0); 46 } 47 48 49 #undef __FUNCT__ 50 #define __FUNCT__ "PetscRandomGetSeed" 51 /*@ 52 PetscRandomGetSeed - Gets the random seed. 53 54 Not collective 55 56 Input Parameters: 57 . r - The random number generator context 58 59 Output Parameter: 60 . seed - The random seed 61 62 Level: intermediate 63 64 Concepts: random numbers^seed 65 66 .seealso: PetscRandomCreate(), PetscRandomSetSeed(), PetscRandomSeed() 67 @*/ 68 PetscErrorCode PetscRandomGetSeed(PetscRandom r,unsigned long *seed) 69 { 70 PetscFunctionBegin; 71 PetscValidHeaderSpecific(r,PETSC_RANDOM_CLASSID,1); 72 if (seed) { 73 PetscValidPointer(seed,2); 74 *seed = r->seed; 75 } 76 PetscFunctionReturn(0); 77 } 78 79 #undef __FUNCT__ 80 #define __FUNCT__ "PetscRandomSetSeed" 81 /*@ 82 PetscRandomSetSeed - Sets the random seed. You MUST call PetscRandomSeed() after this call to have the new seed used. 83 84 Not collective 85 86 Input Parameters: 87 + r - The random number generator context 88 - seed - The random seed 89 90 Level: intermediate 91 92 Usage: 93 PetscRandomSetSeed(r,a positive integer); 94 PetscRandomSeed(r); PetscRandomGetValue() will now start with the new seed. 95 96 PetscRandomSeed(r) without a call to PetscRandomSetSeed() re-initializes 97 the seed. The random numbers generated will be the same as before. 98 99 Concepts: random numbers^seed 100 101 .seealso: PetscRandomCreate(), PetscRandomGetSeed(), PetscRandomSeed() 102 @*/ 103 PetscErrorCode PetscRandomSetSeed(PetscRandom r,unsigned long seed) 104 { 105 PetscErrorCode ierr; 106 107 PetscFunctionBegin; 108 PetscValidHeaderSpecific(r,PETSC_RANDOM_CLASSID,1); 109 r->seed = seed; 110 ierr = PetscInfo1(NULL,"Setting seed to %d\n",(int)seed);CHKERRQ(ierr); 111 PetscFunctionReturn(0); 112 } 113 114 /* ------------------------------------------------------------------- */ 115 #undef __FUNCT__ 116 #define __FUNCT__ "PetscRandomSetTypeFromOptions_Private" 117 /* 118 PetscRandomSetTypeFromOptions_Private - Sets the type of random generator from user options. Defaults to type PETSCRAND48 or PETSCRAND. 119 120 Collective on PetscRandom 121 122 Input Parameter: 123 . rnd - The random number generator context 124 125 Level: intermediate 126 127 .keywords: PetscRandom, set, options, database, type 128 .seealso: PetscRandomSetFromOptions(), PetscRandomSetType() 129 */ 130 static PetscErrorCode PetscRandomSetTypeFromOptions_Private(PetscRandom rnd) 131 { 132 PetscBool opt; 133 const char *defaultType; 134 char typeName[256]; 135 PetscErrorCode ierr; 136 137 PetscFunctionBegin; 138 if (((PetscObject)rnd)->type_name) { 139 defaultType = ((PetscObject)rnd)->type_name; 140 } else { 141 #if defined(PETSC_HAVE_DRAND48) 142 defaultType = PETSCRAND48; 143 #elif defined(PETSC_HAVE_RAND) 144 defaultType = PETSCRAND; 145 #endif 146 } 147 148 if (!PetscRandomRegisterAllCalled) {ierr = PetscRandomRegisterAll();CHKERRQ(ierr);} 149 ierr = PetscOptionsList("-random_type","PetscRandom type","PetscRandomSetType",PetscRandomList,defaultType,typeName,256,&opt);CHKERRQ(ierr); 150 if (opt) { 151 ierr = PetscRandomSetType(rnd, typeName);CHKERRQ(ierr); 152 } else { 153 ierr = PetscRandomSetType(rnd, defaultType);CHKERRQ(ierr); 154 } 155 PetscFunctionReturn(0); 156 } 157 158 #undef __FUNCT__ 159 #define __FUNCT__ "PetscRandomSetFromOptions" 160 /*@ 161 PetscRandomSetFromOptions - Configures the random number generator from the options database. 162 163 Collective on PetscRandom 164 165 Input Parameter: 166 . rnd - The random number generator context 167 168 Options Database: 169 . -random_seed <integer> - provide a seed to the random number generater 170 171 Notes: To see all options, run your program with the -help option. 172 Must be called after PetscRandomCreate() but before the rnd is used. 173 174 Level: beginner 175 176 .keywords: PetscRandom, set, options, database 177 .seealso: PetscRandomCreate(), PetscRandomSetType() 178 @*/ 179 PetscErrorCode PetscRandomSetFromOptions(PetscRandom rnd) 180 { 181 PetscErrorCode ierr; 182 PetscBool set; 183 PetscInt seed; 184 185 PetscFunctionBegin; 186 PetscValidHeaderSpecific(rnd,PETSC_RANDOM_CLASSID,1); 187 188 ierr = PetscObjectOptionsBegin((PetscObject)rnd);CHKERRQ(ierr); 189 190 /* Handle PetscRandom type options */ 191 ierr = PetscRandomSetTypeFromOptions_Private(rnd);CHKERRQ(ierr); 192 193 /* Handle specific random generator's options */ 194 if (rnd->ops->setfromoptions) { 195 ierr = (*rnd->ops->setfromoptions)(rnd);CHKERRQ(ierr); 196 } 197 ierr = PetscOptionsInt("-random_seed","Seed to use to generate random numbers","PetscRandomSetSeed",0,&seed,&set);CHKERRQ(ierr); 198 if (set) { 199 ierr = PetscRandomSetSeed(rnd,(unsigned long int)seed);CHKERRQ(ierr); 200 ierr = PetscRandomSeed(rnd);CHKERRQ(ierr); 201 } 202 ierr = PetscOptionsEnd();CHKERRQ(ierr); 203 ierr = PetscRandomViewFromOptions(rnd,NULL, "-random_view");CHKERRQ(ierr); 204 PetscFunctionReturn(0); 205 } 206 207 #if defined(PETSC_HAVE_AMS) 208 #include <petscviewerams.h> 209 #endif 210 #undef __FUNCT__ 211 #define __FUNCT__ "PetscRandomView" 212 /*@C 213 PetscRandomView - Views a random number generator object. 214 215 Collective on PetscRandom 216 217 Input Parameters: 218 + rnd - The random number generator context 219 - viewer - an optional visualization context 220 221 Notes: 222 The available visualization contexts include 223 + PETSC_VIEWER_STDOUT_SELF - standard output (default) 224 - PETSC_VIEWER_STDOUT_WORLD - synchronized standard 225 output where only the first processor opens 226 the file. All other processors send their 227 data to the first processor to print. 228 229 You can change the format the vector is printed using the 230 option PetscViewerSetFormat(). 231 232 Level: beginner 233 234 .seealso: PetscRealView(), PetscScalarView(), PetscIntView() 235 @*/ 236 PetscErrorCode PetscRandomView(PetscRandom rnd,PetscViewer viewer) 237 { 238 PetscErrorCode ierr; 239 PetscBool iascii; 240 #if defined(PETSC_HAVE_AMS) 241 PetscBool isams; 242 #endif 243 244 PetscFunctionBegin; 245 PetscValidHeaderSpecific(rnd,PETSC_RANDOM_CLASSID,1); 246 PetscValidType(rnd,1); 247 if (!viewer) { 248 ierr = PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)rnd),&viewer);CHKERRQ(ierr); 249 } 250 PetscValidHeaderSpecific(viewer,PETSC_VIEWER_CLASSID,2); 251 PetscCheckSameComm(rnd,1,viewer,2); 252 ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr); 253 #if defined(PETSC_HAVE_AMS) 254 ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERAMS,&isams);CHKERRQ(ierr); 255 #endif 256 if (iascii) { 257 PetscMPIInt rank; 258 ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)rnd),&rank);CHKERRQ(ierr); 259 ierr = PetscViewerASCIISynchronizedAllow(viewer,PETSC_TRUE);CHKERRQ(ierr); 260 ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%D] Random type %s, seed %D\n",rank,((PetscObject)rnd)->type_name,rnd->seed);CHKERRQ(ierr); 261 ierr = PetscViewerFlush(viewer);CHKERRQ(ierr); 262 ierr = PetscViewerASCIISynchronizedAllow(viewer,PETSC_FALSE);CHKERRQ(ierr); 263 #if defined(PETSC_HAVE_AMS) 264 } else if (isams) { 265 if (((PetscObject)rnd)->amsmem == -1) { 266 ierr = PetscObjectViewAMS((PetscObject)rnd,viewer);CHKERRQ(ierr); 267 PetscStackCallAMS(AMS_Memory_add_field,(((PetscObject)rnd)->amsmem,"Low",&rnd->low,1,AMS_DOUBLE,AMS_READ,AMS_COMMON,AMS_REDUCT_UNDEF)); 268 } 269 #endif 270 } 271 PetscFunctionReturn(0); 272 } 273 274 #undef __FUNCT__ 275 #define __FUNCT__ "PetscRandomViewFromOptions" 276 /*@ 277 PetscRandomViewFromOptions - This function visualizes the type and the seed of the generated random numbers based upon user options. 278 279 Collective on PetscRandom 280 281 Input Parameters: 282 . rnd - The random number generator context 283 . title - The title 284 285 Level: intermediate 286 287 .keywords: PetscRandom, view, options, database 288 .seealso: PetscRandomSetFromOptions() 289 @*/ 290 PetscErrorCode PetscRandomViewFromOptions(PetscRandom rnd, const char prefix[], const char optionname[]) 291 { 292 PetscBool flg; 293 PetscViewer viewer; 294 PetscErrorCode ierr; 295 PetscViewerFormat format; 296 297 PetscFunctionBegin; 298 if (prefix) { 299 ierr = PetscOptionsGetViewer(PetscObjectComm((PetscObject)rnd),prefix,optionname,&viewer,&format,&flg);CHKERRQ(ierr); 300 } else { 301 ierr = PetscOptionsGetViewer(PetscObjectComm((PetscObject)rnd),((PetscObject)rnd)->prefix,optionname,&viewer,&format,&flg);CHKERRQ(ierr); 302 } 303 if (flg) { 304 ierr = PetscViewerPushFormat(viewer,format);CHKERRQ(ierr); 305 ierr = PetscRandomView(rnd,viewer);CHKERRQ(ierr); 306 ierr = PetscViewerPopFormat(viewer);CHKERRQ(ierr); 307 ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr); 308 } 309 PetscFunctionReturn(0); 310 } 311 312 #undef __FUNCT__ 313 #define __FUNCT__ "PetscRandomCreate" 314 /*@ 315 PetscRandomCreate - Creates a context for generating random numbers, 316 and initializes the random-number generator. 317 318 Collective on MPI_Comm 319 320 Input Parameters: 321 + comm - MPI communicator 322 323 Output Parameter: 324 . r - the random number generator context 325 326 Level: intermediate 327 328 Notes: 329 The random type has to be set by PetscRandomSetType(). 330 331 This is only a primative "parallel" random number generator, it should NOT 332 be used for sophisticated parallel Monte Carlo methods since it will very likely 333 not have the correct statistics across processors. You can provide your own 334 parallel generator using PetscRandomRegister(); 335 336 If you create a PetscRandom() using PETSC_COMM_SELF on several processors then 337 the SAME random numbers will be generated on all those processors. Use PETSC_COMM_WORLD 338 or the appropriate parallel communicator to eliminate this issue. 339 340 Use VecSetRandom() to set the elements of a vector to random numbers. 341 342 Example of Usage: 343 .vb 344 PetscRandomCreate(PETSC_COMM_SELF,&r); 345 PetscRandomSetType(r,PETSCRAND48); 346 PetscRandomGetValue(r,&value1); 347 PetscRandomGetValueReal(r,&value2); 348 PetscRandomDestroy(&r); 349 .ve 350 351 Concepts: random numbers^creating 352 353 .seealso: PetscRandomSetType(), PetscRandomGetValue(), PetscRandomGetValueReal(), PetscRandomSetInterval(), 354 PetscRandomDestroy(), VecSetRandom(), PetscRandomType 355 @*/ 356 357 PetscErrorCode PetscRandomCreate(MPI_Comm comm,PetscRandom *r) 358 { 359 PetscRandom rr; 360 PetscErrorCode ierr; 361 PetscMPIInt rank; 362 363 PetscFunctionBegin; 364 PetscValidPointer(r,3); 365 *r = NULL; 366 #if !defined(PETSC_USE_DYNAMIC_LIBRARIES) 367 ierr = PetscRandomInitializePackage();CHKERRQ(ierr); 368 #endif 369 370 ierr = PetscHeaderCreate(rr,_p_PetscRandom,struct _PetscRandomOps,PETSC_RANDOM_CLASSID,"PetscRandom","Random number generator","Sys",comm,PetscRandomDestroy,0);CHKERRQ(ierr); 371 372 ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr); 373 374 rr->data = NULL; 375 rr->low = 0.0; 376 rr->width = 1.0; 377 rr->iset = PETSC_FALSE; 378 rr->seed = 0x12345678 + 76543*rank; 379 *r = rr; 380 PetscFunctionReturn(0); 381 } 382 383 #undef __FUNCT__ 384 #define __FUNCT__ "PetscRandomSeed" 385 /*@ 386 PetscRandomSeed - Seed the generator. 387 388 Not collective 389 390 Input Parameters: 391 . r - The random number generator context 392 393 Level: intermediate 394 395 Usage: 396 PetscRandomSetSeed(r,a positive integer); 397 PetscRandomSeed(r); PetscRandomGetValue() will now start with the new seed. 398 399 PetscRandomSeed(r) without a call to PetscRandomSetSeed() re-initializes 400 the seed. The random numbers generated will be the same as before. 401 402 Concepts: random numbers^seed 403 404 .seealso: PetscRandomCreate(), PetscRandomGetSeed(), PetscRandomSetSeed() 405 @*/ 406 PetscErrorCode PetscRandomSeed(PetscRandom r) 407 { 408 PetscErrorCode ierr; 409 410 PetscFunctionBegin; 411 PetscValidHeaderSpecific(r,PETSC_RANDOM_CLASSID,1); 412 PetscValidType(r,1); 413 414 ierr = (*r->ops->seed)(r);CHKERRQ(ierr); 415 ierr = PetscObjectStateIncrease((PetscObject)r);CHKERRQ(ierr); 416 PetscFunctionReturn(0); 417 } 418 419