v4-21-08-2014

[GMRES2stage.git] / code / ex15.c

diff --git a/code/ex15.c b/code/ex15.c
index 0e0a8c467b785a3ebbaae3f4135057fa2abf1390..1fffcbef221d4c25a4fda97db485ed21abf33781 100644 (file)
--- a/code/ex15.c
+++ b/code/ex15.c
@@ -1,5 +1,5 @@
 
-// /home/couturie/work/petsc-3.5.1/arch-linux2-c-debug/bin/mpirun -np 4    ./ex15 -m 400 -n 400
+// /home/couturie/work/petsc-3.5.1/arch-linux2-c-debug/bin/mpirun -np 4    ./ex15 -m 400 -n 400 -ksp_type fgmres
 
 
 
@@ -56,7 +56,7 @@ int KrylovMinimize(Mat A, Vec b, Vec x) {
   //Variables
 
   PetscScalar  gamma, alpha, oldgamma, beta;
-  PetscReal norm=20, Eprecision=1e-8, cgprec=1e-40;     
+  PetscReal norm=20, Eprecision=1e-6, cgprec=1e-40;     
   PetscInt giter=0, ColS=12, col=0, Emaxiter=50000000, iter=0, iterations=15, Iiter=0;
   PetscErrorCode ierr;
   PetscScalar T1, T2;
@@ -120,7 +120,7 @@ int KrylovMinimize(Mat A, Vec b, Vec x) {
 
   //Initializations
   //  ierr = KSPGMRESSetRestart(ksp, 16); CHKERRQ(ierr);
-  ierr = KSPSetTolerances(ksp, 1e-10, 1e-10, PETSC_DEFAULT, 16); CHKERRQ(ierr);
+  ierr = KSPSetTolerances(ksp, 1e-13, 1e-13, PETSC_DEFAULT, 16); CHKERRQ(ierr);
   ierr = KSPSetInitialGuessNonzero(ksp, PETSC_TRUE); CHKERRQ(ierr);
 
 
@@ -146,11 +146,13 @@ int KrylovMinimize(Mat A, Vec b, Vec x) {
 
 
 
-      //Error
+      KSPGetResidualNorm(ksp,&norm);
+
+      /*      //Error
       ierr = VecCopy(x, residu); CHKERRQ(ierr);
       ierr = VecAXPY(residu, -1, x_old); CHKERRQ(ierr);
       ierr = VecNorm(residu, NORM_INFINITY, &norm); CHKERRQ(ierr);
-
+       */
 
 
       ierr = PetscPrintf(PETSC_COMM_WORLD, "Norm of error %g, outer iteration %D\n", norm, giter); CHKERRQ(ierr);
@@ -231,8 +233,8 @@ int KrylovMinimizeLSQR(Mat A, Vec b, Vec x) {
   //Variables
 
   PetscScalar  alpha, beta;
-  PetscReal norm=20, Eprecision=1e-8, tol=1e-40;     
-  PetscInt giter=0, ColS=12, col=0, Emaxiter=50000000, iter=0, iterations=15, Iiter=0;
+  PetscReal norm=20, Eprecision=1e-6, tol=1e-40;     
+  PetscInt giter=0, ColS=12, col=0, Emaxiter=50000000, iter=0, iterations=20, Iiter=0;
   PetscErrorCode ierr;
   PetscScalar T1, T2;
   KSP ksp;
@@ -308,7 +310,7 @@ int KrylovMinimizeLSQR(Mat A, Vec b, Vec x) {
 
   //Initializations
   //  ierr = KSPGMRESSetRestart(ksp, 16); CHKERRQ(ierr);
-  ierr = KSPSetTolerances(ksp, 1e-10, 1e-10, PETSC_DEFAULT, 16); CHKERRQ(ierr);
+  ierr = KSPSetTolerances(ksp, 1e-13, 1e-13, PETSC_DEFAULT, 16); CHKERRQ(ierr);
   ierr = KSPSetInitialGuessNonzero(ksp, PETSC_TRUE); CHKERRQ(ierr);
 
 
@@ -335,11 +337,14 @@ int KrylovMinimizeLSQR(Mat A, Vec b, Vec x) {
 
 
 
+      KSPGetResidualNorm(ksp,&norm);
+
+      /*
       //Error
       ierr = VecCopy(x, residu); CHKERRQ(ierr);
       ierr = VecAXPY(residu, -1, x_old); CHKERRQ(ierr);
       ierr = VecNorm(residu, NORM_INFINITY, &norm); CHKERRQ(ierr);
-
+       */
 
 
       ierr = PetscPrintf(PETSC_COMM_WORLD, "Norm of error %g, outer iteration %D\n", norm, giter); CHKERRQ(ierr);
@@ -419,14 +424,14 @@ int KrylovMinimizeLSQR(Mat A, Vec b, Vec x) {
         VecAYPX(d,-thet,v);       //d = (v - thet * d);
         VecAYPX(d,1/rho,zero_short);     //d=d/ rho;
 
-
+        /*
         if (normar/(norma*normr) <= tol) { // check for convergence in min{|b-A*x|}
           break;
         }
         if (normr <= tolb) {           // check for convergence in A*x=b
           break;
         }
-
+         */
 
         VecAXPY(x_lsqr,phi,d);     // x_lsqr=x_lsqr+phi*d
         normr = abs(s) * normr;
@@ -475,6 +480,10 @@ int main(int argc,char **args)
   ierr = PetscOptionsGetInt(NULL,"-m",&m,NULL);CHKERRQ(ierr);
   ierr = PetscOptionsGetInt(NULL,"-n",&n,NULL);CHKERRQ(ierr);
 
+  PetscMPIInt size;
+  MPI_Comm_size(PETSC_COMM_WORLD,&size);
+  PetscPrintf(PETSC_COMM_WORLD,"Number of processors = %d\n",size);
+
   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
          Compute the matrix and right-hand-side vector that define
          the linear system, Ax = b.
@@ -563,7 +572,7 @@ int main(int argc,char **args)
        to set various options.
   */
   ierr = KSPGetPC(ksp,&pc);CHKERRQ(ierr);
-  ierr = KSPSetTolerances(ksp,1e-9,1e-9,PETSC_DEFAULT,5000000);CHKERRQ(ierr);
+  ierr = KSPSetTolerances(ksp,1e-7,1e-7,PETSC_DEFAULT,5000000);CHKERRQ(ierr);
 
   /*
     Set runtime options, e.g.,
@@ -630,7 +639,7 @@ int main(int argc,char **args)
     VecDuplicate(b,&x2);
     VecDuplicate(b,&sol);
     
-    KrylovMinimize(A, b, x2);
+    KrylovMinimizeLSQR(A, b, x2);
 
 
 
@@ -641,7 +650,7 @@ int main(int argc,char **args)
 
   }
 
-
+  
 
   /*
      Free work space.  All PETSc objects should be destroyed when they