matrix_mult_master.c

A Parallel program to multiply two matrices using Parallel Virtual Machine(PVM).Also a document to i

#include<stdio.h>
#include<pvm3.h>
#include<malloc.h>

#define NPROC 4


main(){
	int mtid,wtid[NPROC],mtype,nrowa,ncola,ncolb,rows,averow,extra,offset,retcode,i,j,ind,nelements;
	int *a,*b,*c;
	char localhost[35];
	int index[NPROC];
	printf("Enter the no of rows and columns of matrix A");
	scanf("%d \t %d",&nrowa,&ncola);
	printf("\nEnter the no of columns of matrix A");
	scanf("%d",&ncolb);
	a = (int*)malloc(nrowa*ncola*sizeof(int));
	b = (int*)malloc(ncola*ncolb*sizeof(int));
	c = (int*)malloc(nrowa*ncolb*sizeof(int));
	mtid = pvm_mytid();

for(i = 0; i < NPROC;i++){
	if(i == 0){
		printf("Enter the localhost name -- must match with PVM conf" );
		scanf("%s",localhost);
		retcode = pvm_spawn("matrix_mult_slave",NULL,PvmTaskHost,localhost,1,&wtid[0]);
	}else 
		retcode = pvm_spawn("matrix_mult_slave",NULL,PvmTaskDefault,"",1,&wtid[i]);
		
}
	averow = nrowa/NPROC;
	extra = nrowa % NPROC;
	offset = 0;
	mtype = 1;
	ind =0;
	index[0]=0;

for(i = 0; i <NPROC; i++){
	rows = (i < extra)? averow+1:averow ;
	retcode = pvm_initsend(PvmDataDefault);
	retcode = pvm_pkint(&rows,1,1);
	retcode = pvm_pkint(&ncola,1,1);
	retcode = pvm_pkint(&ncolb,1,1);
	retcode = pvm_pkint(&a[offset],rows*ncola,1);
	retcode = pvm_pkint(&b[0],ncola*ncolb,1);
	retcode = pvm_send(wtid[i],mtype);
	offset = offset+ rows*ncola;

        if(i!=0)
	{
		ind += rows*ncolb;
		index[i]=ind;
	}

}
	mtype = 2;
	for(i = 0 ; i<NPROC;i++){
	retcode = pvm_recv(-1,mtype);
	retcode = pvm_upkint(&nelements,1,1);
	retcode = pvm_upkint(&c[index[i]],nelements,1);
}
	printf("The product matrix is \n");
	for(i = 0; i<nrowa;i++)
	for(j = 0; j <ncolb;j++)
	printf("%d  ",c[i*ncolb+j]);
	printf("\n");
pvm_exit();

}