1 #include <private/linesearchimpl.h> 2 #include <private/snesimpl.h> 3 4 #undef __FUNCT__ 5 #define __FUNCT__ "SNESLineSearchApply_Basic" 6 static PetscErrorCode SNESLineSearchApply_Basic(SNESLineSearch linesearch) 7 { 8 PetscBool changed_y, changed_w; 9 PetscErrorCode ierr; 10 Vec X, F, Y, W; 11 SNES snes; 12 PetscReal gnorm, xnorm, ynorm, lambda; 13 PetscBool domainerror; 14 15 PetscFunctionBegin; 16 17 ierr = SNESLineSearchGetVecs(linesearch, &X, &F, &Y, &W, PETSC_NULL);CHKERRQ(ierr); 18 ierr = SNESLineSearchGetNorms(linesearch, &xnorm, &gnorm, &ynorm);CHKERRQ(ierr); 19 ierr = SNESLineSearchGetLambda(linesearch, &lambda);CHKERRQ(ierr); 20 ierr = SNESLineSearchGetSNES(linesearch, &snes);CHKERRQ(ierr); 21 ierr = SNESLineSearchSetSuccess(linesearch, PETSC_TRUE);CHKERRQ(ierr); 22 23 /* precheck */ 24 ierr = SNESLineSearchPreCheck(linesearch, &changed_y);CHKERRQ(ierr); 25 26 /* update */ 27 ierr = VecWAXPY(W,-lambda,Y,X);CHKERRQ(ierr); 28 if (linesearch->ops->viproject) { 29 ierr = (*linesearch->ops->viproject)(snes, W);CHKERRQ(ierr); 30 } 31 32 /* postcheck */ 33 ierr = SNESLineSearchPostCheck(linesearch, &changed_y, &changed_w);CHKERRQ(ierr); 34 if (changed_y) { 35 ierr = VecWAXPY(W,-lambda,Y,X);CHKERRQ(ierr); 36 if (linesearch->ops->viproject) { 37 ierr = (*linesearch->ops->viproject)(snes, W);CHKERRQ(ierr); 38 } 39 } 40 ierr = SNESComputeFunction(snes,W,F);CHKERRQ(ierr); 41 ierr = SNESGetFunctionDomainError(snes, &domainerror);CHKERRQ(ierr); 42 if (domainerror) { 43 ierr = SNESLineSearchSetSuccess(linesearch, PETSC_FALSE); 44 PetscFunctionReturn(0); 45 } 46 47 ierr = VecNorm(Y, NORM_2, &linesearch->ynorm);CHKERRQ(ierr); 48 ierr = VecNorm(W, NORM_2, &linesearch->xnorm);CHKERRQ(ierr); 49 if (linesearch->ops->vinorm) { 50 linesearch->fnorm = gnorm; 51 ierr = (*linesearch->ops->vinorm)(snes, F, W, &linesearch->fnorm);CHKERRQ(ierr); 52 } else { 53 ierr = VecNorm(F,NORM_2,&linesearch->fnorm);CHKERRQ(ierr); 54 } 55 56 /* 57 ierr = SNESLineSearchComputeNorms(linesearch);CHKERRQ(ierr); 58 */ 59 60 /* copy the solution over */ 61 ierr = VecCopy(W, X);CHKERRQ(ierr); 62 PetscFunctionReturn(0); 63 } 64 65 #undef __FUNCT__ 66 #define __FUNCT__ "SNESLineSearchCreate_Basic" 67 /*MC 68 SNES_LINESEARCH_BASIC - This routine is not a line search at all; 69 it simply uses the full step. Thus, this routine is intended 70 to serve as a template and is not recommended for general use. 71 72 Level: advanced 73 74 .keywords: SNES, SNESLineSearch, damping 75 76 .seealso: SNESLineSearchCreate(), SNESLineSearchSetType() 77 M*/ 78 PETSC_EXTERN_C PetscErrorCode SNESLineSearchCreate_Basic(SNESLineSearch linesearch) 79 { 80 PetscFunctionBegin; 81 linesearch->ops->apply = SNESLineSearchApply_Basic; 82 linesearch->ops->destroy = PETSC_NULL; 83 linesearch->ops->setfromoptions = PETSC_NULL; 84 linesearch->ops->reset = PETSC_NULL; 85 linesearch->ops->view = PETSC_NULL; 86 linesearch->ops->setup = PETSC_NULL; 87 PetscFunctionReturn(0); 88 } 89