C++ for Scientists - Technische Universität Dresden

Parallelism
Chapter 13
13.1 Multi-Threading
To do!
13.2 Message Passing
13.2.1 Traditional Message Passing
Parallel hello world
#include
#include
int main (int argc, char∗ argv[])
{
MPI Init(&argc, &argv);
std::cout ≪ ”Hello, World!\n”;
MPI Finalize();
}
return 0 ;
#include
#include
int main (int argc, char∗ argv[])
{
MPI Init(&argc, &argv);
int myrank, nprocs;
MPI Comm rank(MPI COMM WORLD, &myrank);
MPI Comm size(MPI COMM WORLD, &nprocs);
std::cout ≪ ”Hello world, I am process number ” ≪ myrank ≪ ” out of ” ≪ nprocs ≪ ”.\n”;
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