Actual source code: fncombine.c

slepc-3.13.2 2020-05-12
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  1: /*
  2:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  3:    SLEPc - Scalable Library for Eigenvalue Problem Computations
  4:    Copyright (c) 2002-2020, Universitat Politecnica de Valencia, Spain

  6:    This file is part of SLEPc.
  7:    SLEPc is distributed under a 2-clause BSD license (see LICENSE).
  8:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  9: */
 10: /*
 11:    A function that is obtained by combining two other functions (either by
 12:    addition, multiplication, division or composition)

 14:       addition:          f(x) = f1(x)+f2(x)
 15:       multiplication:    f(x) = f1(x)*f2(x)
 16:       division:          f(x) = f1(x)/f2(x)      f(A) = f2(A)\f1(A)
 17:       composition:       f(x) = f2(f1(x))
 18: */

 20:  #include <slepc/private/fnimpl.h>
 21:  #include <slepcblaslapack.h>

 23: typedef struct {
 24:   FN            f1,f2;    /* functions */
 25:   FNCombineType comb;     /* how the functions are combined */
 26: } FN_COMBINE;

 28: PetscErrorCode FNEvaluateFunction_Combine(FN fn,PetscScalar x,PetscScalar *y)
 29: {
 31:   FN_COMBINE     *ctx = (FN_COMBINE*)fn->data;
 32:   PetscScalar    a,b;

 35:   FNEvaluateFunction(ctx->f1,x,&a);
 36:   switch (ctx->comb) {
 37:     case FN_COMBINE_ADD:
 38:       FNEvaluateFunction(ctx->f2,x,&b);
 39:       *y = a+b;
 40:       break;
 41:     case FN_COMBINE_MULTIPLY:
 42:       FNEvaluateFunction(ctx->f2,x,&b);
 43:       *y = a*b;
 44:       break;
 45:     case FN_COMBINE_DIVIDE:
 46:       FNEvaluateFunction(ctx->f2,x,&b);
 47:       if (b==0.0) SETERRQ(PETSC_COMM_SELF,1,"Function not defined in the requested value");
 48:       *y = a/b;
 49:       break;
 50:     case FN_COMBINE_COMPOSE:
 51:       FNEvaluateFunction(ctx->f2,a,y);
 52:       break;
 53:   }
 54:   return(0);
 55: }

 57: PetscErrorCode FNEvaluateDerivative_Combine(FN fn,PetscScalar x,PetscScalar *yp)
 58: {
 60:   FN_COMBINE     *ctx = (FN_COMBINE*)fn->data;
 61:   PetscScalar    a,b,ap,bp;

 64:   switch (ctx->comb) {
 65:     case FN_COMBINE_ADD:
 66:       FNEvaluateDerivative(ctx->f1,x,&ap);
 67:       FNEvaluateDerivative(ctx->f2,x,&bp);
 68:       *yp = ap+bp;
 69:       break;
 70:     case FN_COMBINE_MULTIPLY:
 71:       FNEvaluateDerivative(ctx->f1,x,&ap);
 72:       FNEvaluateDerivative(ctx->f2,x,&bp);
 73:       FNEvaluateFunction(ctx->f1,x,&a);
 74:       FNEvaluateFunction(ctx->f2,x,&b);
 75:       *yp = ap*b+a*bp;
 76:       break;
 77:     case FN_COMBINE_DIVIDE:
 78:       FNEvaluateDerivative(ctx->f1,x,&ap);
 79:       FNEvaluateDerivative(ctx->f2,x,&bp);
 80:       FNEvaluateFunction(ctx->f1,x,&a);
 81:       FNEvaluateFunction(ctx->f2,x,&b);
 82:       if (b==0.0) SETERRQ(PETSC_COMM_SELF,1,"Derivative not defined in the requested value");
 83:       *yp = (ap*b-a*bp)/(b*b);
 84:       break;
 85:     case FN_COMBINE_COMPOSE:
 86:       FNEvaluateFunction(ctx->f1,x,&a);
 87:       FNEvaluateDerivative(ctx->f1,x,&ap);
 88:       FNEvaluateDerivative(ctx->f2,a,yp);
 89:       *yp *= ap;
 90:       break;
 91:   }
 92:   return(0);
 93: }

 95: PetscErrorCode FNEvaluateFunctionMat_Combine(FN fn,Mat A,Mat B)
 96: {
 98:   FN_COMBINE     *ctx = (FN_COMBINE*)fn->data;
 99:   PetscScalar    *Aa,*Ba,*Wa,*Za,one=1.0,zero=0.0;
100:   PetscBLASInt   n,ld,ld2,inc=1,*ipiv,info;
101:   PetscInt       m;
102:   Mat            W,Z;

105:   FN_AllocateWorkMat(fn,A,&W);
106:   MatDenseGetArray(A,&Aa);
107:   MatDenseGetArray(B,&Ba);
108:   MatDenseGetArray(W,&Wa);
109:   MatGetSize(A,&m,NULL);
110:   PetscBLASIntCast(m,&n);
111:   ld  = n;
112:   ld2 = ld*ld;

114:   switch (ctx->comb) {
115:     case FN_COMBINE_ADD:
116:       FNEvaluateFunctionMat_Private(ctx->f1,A,W,PETSC_FALSE);
117:       FNEvaluateFunctionMat_Private(ctx->f2,A,B,PETSC_FALSE);
118:       PetscStackCallBLAS("BLASaxpy",BLASaxpy_(&ld2,&one,Wa,&inc,Ba,&inc));
119:       PetscLogFlops(1.0*n*n);
120:       break;
121:     case FN_COMBINE_MULTIPLY:
122:       FN_AllocateWorkMat(fn,A,&Z);
123:       MatDenseGetArray(Z,&Za);
124:       FNEvaluateFunctionMat_Private(ctx->f1,A,W,PETSC_FALSE);
125:       FNEvaluateFunctionMat_Private(ctx->f2,A,Z,PETSC_FALSE);
126:       PetscStackCallBLAS("BLASgemm",BLASgemm_("N","N",&n,&n,&n,&one,Wa,&ld,Za,&ld,&zero,Ba,&ld));
127:       PetscLogFlops(2.0*n*n*n);
128:       MatDenseRestoreArray(Z,&Za);
129:       FN_FreeWorkMat(fn,&Z);
130:       break;
131:     case FN_COMBINE_DIVIDE:
132:       FNEvaluateFunctionMat_Private(ctx->f2,A,W,PETSC_FALSE);
133:       FNEvaluateFunctionMat_Private(ctx->f1,A,B,PETSC_FALSE);
134:       PetscMalloc1(ld,&ipiv);
135:       PetscStackCallBLAS("LAPACKgesv",LAPACKgesv_(&n,&n,Wa,&ld,ipiv,Ba,&ld,&info));
136:       SlepcCheckLapackInfo("gesv",info);
137:       PetscLogFlops(2.0*n*n*n/3.0+2.0*n*n*n);
138:       PetscFree(ipiv);
139:       break;
140:     case FN_COMBINE_COMPOSE:
141:       FNEvaluateFunctionMat_Private(ctx->f1,A,W,PETSC_FALSE);
142:       FNEvaluateFunctionMat_Private(ctx->f2,W,B,PETSC_FALSE);
143:       break;
144:   }

146:   MatDenseRestoreArray(A,&Aa);
147:   MatDenseRestoreArray(B,&Ba);
148:   MatDenseRestoreArray(W,&Wa);
149:   FN_FreeWorkMat(fn,&W);
150:   return(0);
151: }

153: PetscErrorCode FNEvaluateFunctionMatVec_Combine(FN fn,Mat A,Vec v)
154: {
156:   FN_COMBINE     *ctx = (FN_COMBINE*)fn->data;
157:   PetscScalar    *va,*Za;
158:   PetscBLASInt   n,ld,*ipiv,info,one=1;
159:   PetscInt       m;
160:   Mat            Z;
161:   Vec            w;

164:   MatGetSize(A,&m,NULL);
165:   PetscBLASIntCast(m,&n);
166:   ld = n;

168:   switch (ctx->comb) {
169:     case FN_COMBINE_ADD:
170:       VecDuplicate(v,&w);
171:       FNEvaluateFunctionMatVec(ctx->f1,A,w);
172:       FNEvaluateFunctionMatVec(ctx->f2,A,v);
173:       VecAXPY(v,1.0,w);
174:       VecDestroy(&w);
175:       break;
176:     case FN_COMBINE_MULTIPLY:
177:       VecDuplicate(v,&w);
178:       FN_AllocateWorkMat(fn,A,&Z);
179:       FNEvaluateFunctionMat_Private(ctx->f1,A,Z,PETSC_FALSE);
180:       FNEvaluateFunctionMatVec_Private(ctx->f2,A,w,PETSC_FALSE);
181:       MatMult(Z,w,v);
182:       FN_FreeWorkMat(fn,&Z);
183:       VecDestroy(&w);
184:       break;
185:     case FN_COMBINE_DIVIDE:
186:       VecDuplicate(v,&w);
187:       FN_AllocateWorkMat(fn,A,&Z);
188:       FNEvaluateFunctionMat_Private(ctx->f2,A,Z,PETSC_FALSE);
189:       FNEvaluateFunctionMatVec_Private(ctx->f1,A,v,PETSC_FALSE);
190:       PetscMalloc1(ld,&ipiv);
191:       MatDenseGetArray(Z,&Za);
192:       VecGetArray(v,&va);
193:       PetscStackCallBLAS("LAPACKgesv",LAPACKgesv_(&n,&one,Za,&ld,ipiv,va,&ld,&info));
194:       SlepcCheckLapackInfo("gesv",info);
195:       PetscLogFlops(2.0*n*n*n/3.0+2.0*n*n);
196:       VecRestoreArray(v,&va);
197:       MatDenseRestoreArray(Z,&Za);
198:       PetscFree(ipiv);
199:       FN_FreeWorkMat(fn,&Z);
200:       VecDestroy(&w);
201:       break;
202:     case FN_COMBINE_COMPOSE:
203:       FN_AllocateWorkMat(fn,A,&Z);
204:       FNEvaluateFunctionMat_Private(ctx->f1,A,Z,PETSC_FALSE);
205:       FNEvaluateFunctionMatVec_Private(ctx->f2,Z,v,PETSC_FALSE);
206:       FN_FreeWorkMat(fn,&Z);
207:       break;
208:   }
209:   return(0);
210: }

212: PetscErrorCode FNView_Combine(FN fn,PetscViewer viewer)
213: {
215:   FN_COMBINE     *ctx = (FN_COMBINE*)fn->data;
216:   PetscBool      isascii;

219:   PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&isascii);
220:   if (isascii) {
221:     switch (ctx->comb) {
222:       case FN_COMBINE_ADD:
223:         PetscViewerASCIIPrintf(viewer,"  Two added functions f1+f2\n");
224:         break;
225:       case FN_COMBINE_MULTIPLY:
226:         PetscViewerASCIIPrintf(viewer,"  Two multiplied functions f1*f2\n");
227:         break;
228:       case FN_COMBINE_DIVIDE:
229:         PetscViewerASCIIPrintf(viewer,"  A quotient of two functions f1/f2\n");
230:         break;
231:       case FN_COMBINE_COMPOSE:
232:         PetscViewerASCIIPrintf(viewer,"  Two composed functions f2(f1(.))\n");
233:         break;
234:     }
235:     PetscViewerASCIIPushTab(viewer);
236:     FNView(ctx->f1,viewer);
237:     FNView(ctx->f2,viewer);
238:     PetscViewerASCIIPopTab(viewer);
239:   }
240:   return(0);
241: }

243: static PetscErrorCode FNCombineSetChildren_Combine(FN fn,FNCombineType comb,FN f1,FN f2)
244: {
246:   FN_COMBINE     *ctx = (FN_COMBINE*)fn->data;

249:   ctx->comb = comb;
250:   PetscObjectReference((PetscObject)f1);
251:   FNDestroy(&ctx->f1);
252:   ctx->f1 = f1;
253:   PetscLogObjectParent((PetscObject)fn,(PetscObject)ctx->f1);
254:   PetscObjectReference((PetscObject)f2);
255:   FNDestroy(&ctx->f2);
256:   ctx->f2 = f2;
257:   PetscLogObjectParent((PetscObject)fn,(PetscObject)ctx->f2);
258:   return(0);
259: }

261: /*@
262:    FNCombineSetChildren - Sets the two child functions that constitute this
263:    combined function, and the way they must be combined.

265:    Logically Collective on fn

267:    Input Parameters:
268: +  fn   - the math function context
269: .  comb - how to combine the functions (addition, multiplication, division or composition)
270: .  f1   - first function
271: -  f2   - second function

273:    Level: intermediate

275: .seealso: FNCombineGetChildren()
276: @*/
277: PetscErrorCode FNCombineSetChildren(FN fn,FNCombineType comb,FN f1,FN f2)
278: {

286:   PetscTryMethod(fn,"FNCombineSetChildren_C",(FN,FNCombineType,FN,FN),(fn,comb,f1,f2));
287:   return(0);
288: }

290: static PetscErrorCode FNCombineGetChildren_Combine(FN fn,FNCombineType *comb,FN *f1,FN *f2)
291: {
293:   FN_COMBINE     *ctx = (FN_COMBINE*)fn->data;

296:   if (comb) *comb = ctx->comb;
297:   if (f1) {
298:     if (!ctx->f1) {
299:       FNCreate(PetscObjectComm((PetscObject)fn),&ctx->f1);
300:       PetscLogObjectParent((PetscObject)fn,(PetscObject)ctx->f1);
301:     }
302:     *f1 = ctx->f1;
303:   }
304:   if (f2) {
305:     if (!ctx->f2) {
306:       FNCreate(PetscObjectComm((PetscObject)fn),&ctx->f2);
307:       PetscLogObjectParent((PetscObject)fn,(PetscObject)ctx->f2);
308:     }
309:     *f2 = ctx->f2;
310:   }
311:   return(0);
312: }

314: /*@
315:    FNCombineGetChildren - Gets the two child functions that constitute this
316:    combined function, and the way they are combined.

318:    Not Collective

320:    Input Parameter:
321: .  fn   - the math function context

323:    Output Parameters:
324: +  comb - how to combine the functions (addition, multiplication, division or composition)
325: .  f1   - first function
326: -  f2   - second function

328:    Level: intermediate

330: .seealso: FNCombineSetChildren()
331: @*/
332: PetscErrorCode FNCombineGetChildren(FN fn,FNCombineType *comb,FN *f1,FN *f2)
333: {

338:   PetscUseMethod(fn,"FNCombineGetChildren_C",(FN,FNCombineType*,FN*,FN*),(fn,comb,f1,f2));
339:   return(0);
340: }

342: PetscErrorCode FNDuplicate_Combine(FN fn,MPI_Comm comm,FN *newfn)
343: {
345:   FN_COMBINE     *ctx = (FN_COMBINE*)fn->data,*ctx2 = (FN_COMBINE*)(*newfn)->data;

348:   ctx2->comb = ctx->comb;
349:   FNDuplicate(ctx->f1,comm,&ctx2->f1);
350:   FNDuplicate(ctx->f2,comm,&ctx2->f2);
351:   return(0);
352: }

354: PetscErrorCode FNDestroy_Combine(FN fn)
355: {
357:   FN_COMBINE     *ctx = (FN_COMBINE*)fn->data;

360:   FNDestroy(&ctx->f1);
361:   FNDestroy(&ctx->f2);
362:   PetscFree(fn->data);
363:   PetscObjectComposeFunction((PetscObject)fn,"FNCombineSetChildren_C",NULL);
364:   PetscObjectComposeFunction((PetscObject)fn,"FNCombineGetChildren_C",NULL);
365:   return(0);
366: }

368: SLEPC_EXTERN PetscErrorCode FNCreate_Combine(FN fn)
369: {
371:   FN_COMBINE     *ctx;

374:   PetscNewLog(fn,&ctx);
375:   fn->data = (void*)ctx;

377:   fn->ops->evaluatefunction          = FNEvaluateFunction_Combine;
378:   fn->ops->evaluatederivative        = FNEvaluateDerivative_Combine;
379:   fn->ops->evaluatefunctionmat[0]    = FNEvaluateFunctionMat_Combine;
380:   fn->ops->evaluatefunctionmatvec[0] = FNEvaluateFunctionMatVec_Combine;
381:   fn->ops->view                      = FNView_Combine;
382:   fn->ops->duplicate                 = FNDuplicate_Combine;
383:   fn->ops->destroy                   = FNDestroy_Combine;
384:   PetscObjectComposeFunction((PetscObject)fn,"FNCombineSetChildren_C",FNCombineSetChildren_Combine);
385:   PetscObjectComposeFunction((PetscObject)fn,"FNCombineGetChildren_C",FNCombineGetChildren_Combine);
386:   return(0);
387: }