kml_fft(f)_mpi_plan_dft_r2c_3d

接口定义

C interface：

kml_fft_plan kml_fft_mpi_plan_dft_r2c_3d(int n0, int n1, int n2, double *in, kml_fft_complex *out, MPI_comm comm, unsigned flags);

kml_fftf_plan kml_fftf_mpi_plan_dft_r2c_3d(int n0, int n1, int n2, float *in, kml_fftf_complex *out, MPI_comm comm, unsigned flags);

返回值

函数返回一个kml_fft(f)_plan类型的结构体指针。将该对象作为参数传入kml_fft(f/h)_execute函数中使用，将对当前提供的输入in和输出out执行FFT变换；另外，也可以通过将该对象作为参数传入kml_fft(f/h)_execute_dft_r2c函数中以对新的输入in和输出out执行FFT变换。

如果函数返回非空指针，则表示plan执行成功，否则表示执行失败。

参数

依赖

C: "kfft-mpi.h"

示例

C interface：

    const ptrdiff_t N0 = 4, N1 = 4, N2 = 4;
    kml_fft_plan plan;
    ptrdiff_t alloc_local, local_n0, local_0_start;
 
    MPI_Init(&argc, &argv);
    MPI_Comm comm = MPI_COMM_WORLD;
    kml_fft_mpi_init();
    double *in = NULL;
    kml_fft_complex *out = NULL;
 
    /* get local data size and allocate */
    alloc_local = kml_fft_mpi_local_size_3d(N0, N1, N2, comm, &local_n0, &local_0_start);
    if (alloc_local == -1) {
        printf("[%s][%d] allocate size fail!!!\n", __func__, __LINE__);
    }
    in = (double *)kml_fft_malloc(sizeof(double) * alloc_local * 2);
    if (in == NULL) {
        printf("[%s][%d] malloc memory fail!!!\n", __func__, __LINE__);
    }
    out = (kml_fft_complex *)kml_fft_malloc(sizeof(kml_fft_complex) * alloc_local);
    if (out == NULL) {
        printf("[%s][%d] malloc memory fail!!!\n", __func__, __LINE__);
    }
 
    /* create plan for in-place forward DFT */
    plan = kml_fft_mpi_plan_dft_r2c_3d(N0, N1, N2, in, out, comm, KML_FFT_ESTIMATE);    
            
    /* compute transforms, in-place, as many times as desired */
    kml_fft_execute(plan);
 
    kml_fft_destroy_plan(plan);
    kml_fft_mpi_cleanup();
 
    MPI_Finalize();