MPI_BCast不适用于MPI_Comm_Split

问：

我是 MPI 编程的菜鸟，所以我尝试实现一个小程序，将所有进程拆分为一个带有新通信器的组。

#include <mpi.h>
#include <stdio.h>
#include <string.h>

int main(int argc, char **argv) {
    MPI_Init(&argc, &argv);

    int rank, size;
    MPI_Comm_rank(MPI_COMM_WORLD, &rank);
    MPI_Comm_size(MPI_COMM_WORLD, &size);

    MPI_Comm central_server_comm, intermediary_server_comm, lolcal_devices_comm;
    int new_color;

    if (rank == 0) {
        // The process with rank 0 is the central server
        new_color = 0;
    } else if (rank == 1) {
        // The process with the rank 1 is the intermediary server
        new_color = 1;
    } else {
        // The other processes are local devices
        new_color = 2;
    }

    MPI_Comm_split(MPI_COMM_WORLD, new_color, rank, &central_server_comm);

   float message[4]; // Initializes an array of floating-point numbers

    if (new_color == 0) {
        
        // This is the central server
        printf("I am the central server. Rank %d of %d.\n", rank, size);
        // Initialize the array with the desired numbers
        message[0] = 1.0;
        message[1] = 2.0;
        message[2] = 3.0;
        message[3] = 4.0;
        MPI_Send(message, 4, MPI_FLOAT, 1, 0, MPI_COMM_WORLD); // Broadcast to everyone
    } else if (new_color == 1) {
        // This is an intermediary server
        printf("I am the intermediary server. Rank %d of %d.\n", rank, size);
        MPI_Bcast(message, 4, MPI_FLOAT, 0, central_server_comm); // Ricevi il messaggio da server centrale
        printf("Message received from central server: %f %f %f %f\n", message[0], message[1], message[2], message[3]);
    } else {
        //This is a local device
        printf("I am a local device. Rank %d of %d.\n", rank, size);
        MPI_Bcast(message, 4, MPI_FLOAT, 0, central_server_comm); // Ricevi il messaggio da server intermedio
        printf("Message received from intermediary server: %f %f %f %f\n", message[0], message[1], message[2], message[3]);
    }

    MPI_Comm_free(&central_server_comm);

    MPI_Finalize();
    return 0;
}

我也让一个错误的输出

我希望秩 = 0 的进程将数据发送到秩 = 1 的进程，最后一个进程将数据广播到所有其他进程，但是当我尝试发送整数数据时，一切正常，但是当我尝试发送其他类型的数据（如 float 或 char）时，它会发送 null valure（float 为 0.0，char 为 “ ”。我把代码放在这里。我希望有人能帮助我。我认为我在功能mpi_comm_split上弄错了什么，但我不知道是什么。