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Datatypes

C

MPI_C_COMPLEX

Definition

MPI_C_COMPLEX is an MPI_Datatype that represents a complex type in MPI, it corresponds to a float _Complex in C.

Example

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#include <stdio.h>
#include <stdlib.h>
#include <complex.h>
#include <mpi.h>

/**
 * @brief Illustrate how to communicate a complex float between 2 MPI processes.
 * @details This application is meant to be run with 2 MPI processes: 1 sender
 * and 1 receiver. The former sends a complex float to the latter, which prints
 * it.
 **/
int main(int argc, char* argv[])
{
    MPI_Init(&argc, &argv);

    // Check that 2 MPI processes are used.
    int size;
    MPI_Comm_size(MPI_COMM_WORLD, &size);
    if(size != 2)
    {
        printf("This application is meant to be run with 2 MPI processes.\n");
        MPI_Abort(MPI_COMM_WORLD, EXIT_FAILURE);
    }

    // Get my rank and do the corresponding job.
    enum role_ranks { SENDER, RECEIVER };
    int my_rank;
    MPI_Comm_rank(MPI_COMM_WORLD, &my_rank);
    switch(my_rank)
    {
        case SENDER:
        {
            // Send the complex
            float _Complex complexToSend = I * I;
            printf("[MPI process %d] I send complex: %.1f+%.1fi.\n", my_rank, crealf(complexToSend), cimagf(complexToSend));
            MPI_Ssend(&complexToSend, 1, MPI_C_COMPLEX, RECEIVER, 0, MPI_COMM_WORLD);
            break;
        }
        case RECEIVER:
        {
            // Receive the complex
            float _Complex complexReceived;
            MPI_Recv(&complexReceived, 1, MPI_C_COMPLEX, SENDER, 0, MPI_COMM_WORLD, MPI_STATUS_IGNORE);
            printf("[MPI process %d] I received complex: %.1f+%.1fi.\n", my_rank, crealf(complexReceived), cimagf(complexReceived));
            break;
        }
    }

    MPI_Finalize();

    return EXIT_SUCCESS;
}

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#include <stdio.h>
#include <stdlib.h>
#include <complex.h>
#include <mpi.h>

/**
 * @brief Illustrate how to communicate an array of floats between 2 MPI
 * processes.
 * @details This application is meant to be run with 2 MPI processes: 1 sender
 * and 1 receiver. The former sends an array of floats to the latter, which
 * prints it.
 **/
int main(int argc, char* argv[])
{
    MPI_Init(&argc, &argv);

    // Check that 2 MPI processes are used.
    int size;
    MPI_Comm_size(MPI_COMM_WORLD, &size);
    if(size != 2)
    {
        printf("This application is meant to be run with 2 MPI processes.\n");
        MPI_Abort(MPI_COMM_WORLD, EXIT_FAILURE);
    }

    // Get my rank and do the corresponding job.
    enum role_ranks { SENDER, RECEIVER };
    int my_rank;
    MPI_Comm_rank(MPI_COMM_WORLD, &my_rank);
    switch(my_rank)
    {
        case SENDER:
        {
            // Send the complexes
            float _Complex complexesToSend[2] = { I * I, 2 * I * I };
            printf("[MPI process %d] I send complexes: %.1f+%.1fi and %.1f+%.1fi.\n", my_rank, crealf(complexesToSend[0]), cimagf(complexesToSend[0]), crealf(complexesToSend[1]), cimagf(complexesToSend[1]));
            MPI_Ssend(complexesToSend, 2, MPI_C_COMPLEX, RECEIVER, 0, MPI_COMM_WORLD);
            break;
        }
        case RECEIVER:
        {
            // Receive the complexes
            float _Complex complexesReceived[2];
            MPI_Recv(complexesReceived, 2, MPI_C_COMPLEX, SENDER, 0, MPI_COMM_WORLD, MPI_STATUS_IGNORE);
            printf("[MPI process %d] I received complexes: %.1f+%.1fi and %.1f+%.1fi.\n", my_rank, crealf(complexesReceived[0]), cimagf(complexesReceived[0]), crealf(complexesReceived[1]), cimagf(complexesReceived[1]));
            break;
        }
    }

    MPI_Finalize();

    return EXIT_SUCCESS;
}