用mpi數據類型排列3-d陣列

Question

假設你有一個3d數組A [I] [J] [K]，但是你想將它排列成B [J] [K] [I]。

此問題與此處討論的二維陣列轉置問題類似，但不同於此處： Can you transpose array when sending using MPI_Type_create_subarray?。

MPI標準提供多維數組操作的示例與用戶定義數據類型，而不是該特定情況下：http://www.mpi-forum.org/docs/mpi-11-html/node61.html

Answer 1

做的方式，這是與MPI_TYPE_VECTOR和MPI_TYPE_CREATE_HVECTOR，但魔鬼在細節。現在

/* data[I][J][K] is I by J by K (stored in array 'dim_sizes[] = {I, J, K}' 
    and we want permuted[J][K][I] */ 

/* new innermost dimension is I items, strided across the old JK face*/ 
MPI_Type_vector(dim_sizes[0], 1, dim_sizes[1]*dim_sizes[2], 
    MPI_DOUBLE, &one_d); 
MPI_Type_commit(&one_d); 

/* new middle dimenson is K items, strided over the K row, which isn't 
* actually a stride in this case. We use hvector here because we 
* operate directly in terms of array items */ 
MPI_Type_create_hvector(dim_sizes[2], 1, sizeof(double), one_d, &two_d); 
MPI_Type_commit(&two_d); 

/* new outermost dimension is J items, strided over the old J row */ 
MPI_Type_create_hvector(dim_sizes[1], 1, dim_sizes[2]*sizeof(double), two_d, 
    &transposed_type); 
MPI_Type_commit(&transposed_type); 

可以喂transposed_type您發送/接收來電或使您的MPI文件視圖。