mpi pi darts 2 .c - /* COMP 137 Spring 2020 - April 16 -...

/* COMP 137 Spring 2020 - April 16 - In-class MPI Lab 2
* filename: mpi_pi_darts.c
*
* Purpose: Estimate the value of PI using the dartboard method.
* Parallelized as MPI processes.
*
* Today's exercise: This is currently a serial program.
* Parallelize it with MPI.
*/
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <time.h>
#include <mpi.h>
/* global values */
long dart_count = 1000000000;
/* forward reference */
long throwDarts(long num_darts, double radius);
/*--------------------------------------------------------------------*/
int main(int argc, char* argv[])
{
int rank; // rank of this process
int comm_size; // number of processes
double PI;
int source;
long total_darts, total_hits;
long my_darts, my_hits;
double start , finish ;
long comm_buff[2];
double MPI_Wtime(void);
/* ICE10: initialize MPI, determine number of processes and rank. */
MPI_Init(&argc,&argv);/////////////////////////////////////////////////////////////
///////
MPI_Comm_size(MPI_COMM_WORLD, &comm_size);
MPI_Comm_rank(MPI_COMM_WORLD, &rank);
printf ("MPI task %d has started...\n", rank);
/* Set seed for random number generator equal to rank ID */
srand(rank);
///srand(time(0)); /* seed the random number generator
*/ ////////////////////////////////////////////////////////////////////
my_darts = dart_count / comm_size;
my_hits = throwDarts(my_darts, 1.0);
if(rank != 0)
{
/* ICE10: If this is not process 0,
* send my_darts and my_hits to process 0.*/
// MPI_Send(&my_darts, 1, MPI_LONG, 0, 0, MPI_COMM_WORLD);