#include "petsc.h"


#define MAX_STR_SIZE 1024

// Main program
int main(int argc,char *argv[])
{
	char auxstr[MAX_STR_SIZE];
	Mat G;

	PetscErrorCode iErr,ierr = 0;
	PetscBool	flag;

	PetscInt Np = 0;

	// MATRIX SIZE DECLARATION
	PetscInt
	  nRows = 300, //5085,
	nCols = 200; //737352;
	
	PetscViewer		binv;

	int rVal = 0;

	iErr = PetscInitialize(&argc,&argv,PETSC_NULL,0); CHKERRQ(iErr);

		iErr = PetscOptionsGetString(PETSC_NULL,"--mtx-file",auxstr,MAX_STR_SIZE,&flag); CHKERRQ(iErr);

                MatCreateMPIDense(PETSC_COMM_WORLD,PETSC_DECIDE,PETSC_DECIDE,nRows,nCols,PETSC_NULL,&G);CHKERRQ(ierr);


		PetscPrintf(PETSC_COMM_WORLD,"Matrix created successfully!\n");

		iErr = MatAssemblyBegin(G,MAT_FINAL_ASSEMBLY); CHKERRQ(ierr);
		iErr = MatAssemblyEnd(G,MAT_FINAL_ASSEMBLY); CHKERRQ(ierr);

		PetscPrintf(PETSC_COMM_WORLD,"Matrix assembled successfully!\n");


		iErr = PetscViewerBinaryOpen(PETSC_COMM_WORLD,auxstr,FILE_MODE_WRITE,&binv); CHKERRQ(iErr);
		iErr = PetscViewerPushFormat(binv,PETSC_VIEWER_NATIVE); CHKERRQ(iErr);
		iErr = MatView(G,binv); CHKERRQ(iErr);
		iErr = PetscViewerDestroy(&binv); CHKERRQ(iErr);

	PetscPrintf(PETSC_COMM_WORLD,"Matrix successfully written: now cleaning up and exiting.\n");

	iErr = MatDestroy(&G); CHKERRQ(iErr);

	ierr = MatCreate(PETSC_COMM_WORLD,&G);CHKERRQ(ierr);
	ierr = MatSetType(G,MATDENSE);CHKERRQ(ierr);
iErr = PetscViewerBinaryOpen(PETSC_COMM_WORLD,auxstr,FILE_MODE_READ,&binv); CHKERRQ(iErr);
		iErr = PetscViewerPushFormat(binv,PETSC_VIEWER_NATIVE); CHKERRQ(iErr);
		iErr = MatLoad(G,binv); CHKERRQ(iErr);
		iErr = PetscViewerDestroy(&binv); CHKERRQ(iErr);
		MatDestroy(&G);


	PetscFinalize();

	return( rVal );
}