The following is a list of C, C++ and Fortran compilers available on the CHPC cluster:

• icc (for C and C++)
• ifort

• gcc
• g++
• gfortran

The module command provides a convenient mechanism for managing which environment variables are set in your shell session. The following is a list of the basic usage of the module command:

• Check which modules are available

  module avail

• Add a module to the current environment

  module add <module>

• Show loaded modules

  module list

• Remove a module from the environment

  module remove <module>

  or

  module rm <module>

#include <stdio.h>
 
int main()
{
    printf("Hello World");
    return 0;
}

#include <stdlib.h>
#include <stdio.h>
#include <mpi.h>
 
int
main(argc, argv)
 
int                     argc;
char                    *argv[];
 
{
        int             rank, size, len;
        char            name[MPI_MAX_PROCESSOR_NAME];
 
        MPI_Init(&argc, &argv);
        MPI_Comm_rank(MPI_COMM_WORLD, &rank);
        MPI_Comm_size(MPI_COMM_WORLD, &size);
 
        MPI_Get_processor_name(name, &len);
        printf ("Hello world! I'm %d of %d on %s\n", rank, size, name);
 
        MPI_Finalize();
        exit(0);
}

PROGRAM Hello
    PRINT *, "Hello World"
END PROGRAM Hello

The following code snippets demonstrate how to compile the above code examples use the GNU compiler suite:

gcc -o hello hello.c

mpicc -o hello hello.c

gfortran -o hello hello.f90

The above compilers include support for OpenMP. To compile an OpenMP code add the -fopenmp option. For example:

gcc -o mp_hello -fopenmp mp_hello.c

code from https://computing.llnl.gov/tutorials/openMP/samples/C/omp_hello.c

The following code snippets demonstrate how to compile OpenMP examples with the Intel compilers:

icc -openmp omp_hello.c -o hello

ifort -openmp omp_hello.f -o hello

An example of compiling and executing a simple Java program:

 
public class MyFirstJavaProgram {
  public static void main(String []args) {
    System.out.println("Hello World"); // prints Hello World
  }
}

To compile this, make sure you have the java module loaded, then:

javac MyFirstJavaProgram.java

A bytecode-compiled file should be created, named MyFirstJavaProgram.class

To execute it, run as follows:

java MyFirstJavaProgram

MPI (Message Passing Interface – http://www.open-mpi.org) is provided using the OpenMPI libraries. To compile MPI code use the mpicc or mpif90 compilers.

To run an MPI job see the man pages for PBS Pro. On the login node, type “man qsub”. To obtain an interactive node, use qsub -I The login node prevents long-running processes therefore an interactive node is useful for compilations and builds. To test your code, load the module you want to use first, and then compile your code with it:

$mpicc -o bin/test src/hello_world.c

To test it:

mpirun -np 8 bin/test

You should see something similar to:

Hello world! I'm 7 of 8 on cnode-2-6
Hello world! I'm 6 of 8 on cnode-2-6
Hello world! I'm 5 of 8 on cnode-2-6
Hello world! I'm 1 of 8 on cnode-2-6
Hello world! I'm 0 of 8 on cnode-2-6
Hello world! I'm 3 of 8 on cnode-2-6
Hello world! I'm 2 of 8 on cnode-2-6
Hello world! I'm 4 of 8 on cnode-2-6