#include "hpc_petsc_bench.h"

static const char help[] = "Solve Ax=b using GMRES, options array_in_received_buffer\n\

\t-mfile matrix_file (matrix file in PETSc bin format, this is mandatory)\n\

\t-bfile right_and_side_file (also in PETSc bin format)\n\

\t-xfile initial_solution_file (in PETSc bin format)\n";

int main(int argc, char **argv){

PetscErrorCode ierr;

Vec x,b;

Mat A;

KSP ksp;

ierr=PetscInitialize(&argc,&argv,PETSC_NULL,PETSC_NULL);CHKERRQ(ierr);

PetscPrintf(PETSC_COMM_WORLD,"]> Initializing PETSc/SLEPc\n");

/*Load data*/

ierr=loadInputs(&A,&b,&x);CHKERRQ(ierr);

PetscPrintf(PETSC_COMM_WORLD,"]> Data loaded\n");

/*Create the KSP context and setup*/

ierr = KSPCreate(PETSC_COMM_WORLD,&ksp);CHKERRQ(ierr);

ierr = KSPSetType(ksp,KSPFGMRES);CHKERRQ(ierr);

ierr = KSPSetOperators(ksp,A,A,DIFFERENT_NONZERO_PATTERN);CHKERRQ(ierr);

ierr = KSPSetFromOptions(ksp);CHKERRQ(ierr);

ierr = KSPSetUp(ksp);CHKERRQ(ierr);

PetscPrintf(PETSC_COMM_WORLD,"]> Krylov Solver settings done\n");

/*Solve the system*/

PetscPrintf(PETSC_COMM_WORLD,"]> Krylov Solver Launching solving process\n");

ierr = KSPSolve(ksp, b, x); CHKERRQ(ierr);

PetscPrintf(PETSC_COMM_WORLD,"]> Krylov Solver System solved\n");

/*Clean*/

ierr = KSPDestroy(&ksp);CHKERRQ(ierr);

ierr = VecDestroy(&b);CHKERRQ(ierr);

ierr = VecDestroy(&x);CHKERRQ(ierr);

ierr = MatDestroy(&A);CHKERRQ(ierr);

PetscPrintf(PETSC_COMM_WORLD,"]> Cleaned structures, finalizing\n");

/*Finalize PETSc*/

PetscFinalize();

return 0;

}

PetscErrorCode loadInputs(Mat * A, Vec * b, Vec * x){

PetscErrorCode ierr;

PetscInt sizex,sizey;

char bfile[]="-bfile";

char xfile[]="-xfile";

//load data files

ierr=loadMatrix(A);CHKERRQ(ierr);

ierr=loadVector(bfile,b);CHKERRQ(ierr);

if(*b==NULL) {

PetscPrintf(PETSC_COMM_WORLD,"]> Creating vector b\n");

ierr=MatGetSize(*A,&sizex,&sizey);CHKERRQ(ierr);

ierr=generateVectorRandom(sizex,b);CHKERRQ(ierr);

}

ierr=loadVector(xfile,x);CHKERRQ(ierr);

if(*x==NULL) {

PetscPrintf(PETSC_COMM_WORLD,"]> Creating vector x\n");

ierr=MatGetSize(*A,&sizex,&sizey);CHKERRQ(ierr);

ierr=generateVectorRandom(sizex,x);CHKERRQ(ierr);

}

return 0;

}

PetscErrorCode loadMatrix(Mat * A){

char file[PETSC_MAX_PATH_LEN];

char err[PETSC_MAX_PATH_LEN];

PetscErrorCode ierr;

PetscBool flag;

PetscViewer fd;

PetscInt sizex,sizey;

/*check args, if no matrix then no work... matrix file is mandatory*/

ierr=PetscOptionsGetString(PETSC_NULL,"-mfile",file,PETSC_MAX_PATH_LEN-1,&flag);CHKERRQ(ierr);

if (!flag) {

sprintf(err,"Error : mfile is not properly set -> %s\n",file);

SETERRQ(PETSC_COMM_WORLD,(PetscErrorCode)83,err);

}

/* read matrix file */

PetscPrintf(PETSC_COMM_WORLD,"Loading Matrix : %s\n",file);

ierr=MatCreate(PETSC_COMM_WORLD,A);CHKERRQ(ierr);

ierr=MatSetType(*A,MATAIJ);CHKERRQ(ierr);

ierr=PetscViewerBinaryOpen(PETSC_COMM_WORLD,file,FILE_MODE_READ,&fd);CHKERRQ(ierr);

ierr=MatLoad(*A,fd);CHKERRQ(ierr);

ierr=PetscViewerDestroy(&fd);CHKERRQ(ierr);

ierr=MatGetSize(*A,&sizex,&sizey);CHKERRQ(ierr);

PetscPrintf(PETSC_COMM_WORLD,"Loaded Matrix of size : %d %d\n",sizex,sizey);

return 0;

}

PetscErrorCode loadVector(char * type_v,Vec * b){

char file[PETSC_MAX_PATH_LEN];

char err[PETSC_MAX_PATH_LEN];

PetscErrorCode ierr;

PetscBool flag;

PetscViewer fd;

PetscInt size;

// check if there is a vec file, vector is not mandatory

ierr=PetscOptionsGetString(PETSC_NULL,type_v,file,PETSC_MAX_PATH_LEN-1,&flag);CHKERRQ(ierr);

if (!flag) {

PetscPrintf(PETSC_COMM_WORLD,"Error : %s is not properly set\n",type_v);

*b = NULL;

}else{

PetscPrintf(PETSC_COMM_WORLD,"Loading Vector : %s\n",file);

ierr=PetscViewerBinaryOpen(PETSC_COMM_WORLD,file,FILE_MODE_READ,&fd);CHKERRQ(ierr);

ierr=VecLoad(*b,fd);CHKERRQ(ierr);

ierr=PetscViewerDestroy(&fd);CHKERRQ(ierr);

ierr=VecGetSize(*b,&size);CHKERRQ(ierr);

PetscPrintf(PETSC_COMM_WORLD,"Loaded Vector of size : %d\n",size);

}

return 0;

}

PetscErrorCode generateVectorRandom(int size, Vec * v){

PetscErrorCode ierr;

ierr=PetscPrintf(PETSC_COMM_WORLD,"Generating Vector \n");CHKERRQ(ierr);

ierr=generateVector(size,v);CHKERRQ(ierr);

ierr=VecSetRandom(*v,PETSC_NULL);CHKERRQ(ierr);

PetscPrintf(PETSC_COMM_WORLD,"Generated Random Vector of size : %d\n",size);

return 0;

}

PetscErrorCode generateVectorNorm(int size, Vec * v){

PetscScalar scal;

PetscErrorCode ierr;

ierr=PetscPrintf(PETSC_COMM_WORLD,"Generating Vector \n");CHKERRQ(ierr);

ierr=generateVector(size,v);CHKERRQ(ierr);

scal=1.0/size;

ierr=VecSet(*v,scal);CHKERRQ(ierr);

PetscPrintf(PETSC_COMM_WORLD,"Generated Norm Vector of size : %d\n",size);

return 0;

}

PetscErrorCode generateVector(int size, Vec * v){

PetscErrorCode ierr;

ierr=VecCreate(PETSC_COMM_WORLD,v);CHKERRQ(ierr);

ierr=VecSetSizes(*v,PETSC_DECIDE,size);CHKERRQ(ierr);

ierr=VecSetFromOptions(*v);CHKERRQ(ierr);

/*initiate the vector to its norm*/

return 0;

}