迁移步骤

C语言迁移步骤

MUMPS提供C接口，KML_SOLVER同样也提供了C接口，但接口名及接收参数不一致，需要进行对应功能的切换，举例如下：

1. 迁移前：

   int n = 8;
   int nnz = 17;
   int irn[17] = {1, 1, 1, 2, 2, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 8};
   int jcn[17] = {1, 4, 5, 2, 3, 4, 6, 3, 8, 4, 7, 5, 6, 6, 8, 7, 8};
   double a[17] = {1.0, 1.0, 2.0, 9.0, 2.0, 1.0, -3.0, 3.0, 2.0, 9.0, -5.0, 6.0, 1.0, 4.0, 1.0, 7.0, 2.0};
   double b[8] = {4.0, 9.0, 7.0, 6.0, 9.0, 3.0, 2.0, 5.0};
   
   MPI_Init(NULL, NULL);
   int size, rank;
   MPI_Comm_size(MPI_COMM_WORLD, &size);
   MPI_Comm_rank(MPI_COMM_WORLD, &rank);
   
   DMUMPS_STRUC_C id;
   id.par = 1;
   id.sym = 1;
   id.job = -1;
   
   dmumps_c(&id);//Init
   
   if(rank == 0) {
           id.n = n;
           id.nnz = nnz;
           id.irn = irn;
           id.jcn = jcn;
           id.a = a;
           id.rhs = b;
   }
   #define ICNTL(I) icntl[(I)-1]
   id.ICNTL(1)=-1; id.ICNTL(2)=-1; id.ICNTL(3)=-1; id.ICNTL(4)=0;
   
   id.job = 6;
   dmumps_c(&id);//Analyze + Factorize + Solve
   if (id.infog[0]<0) {
       printf(" (PROC %d) ERROR RETURN: \tINFOG(1)= %d\n\t\t\t\tINFOG(2)= %d\n",
                   rank, id.infog[0], id.infog[1]);
   }
   
   if(rank == 0) {
      for (int i = 0; i < n; i++) {
          printf("%lf ", b[i]);
      }
      printf("\n");
   }
   
   id.job = -2;
   dmumps_c(&id); //clean
   
   MPI_Finalize();

   迁移后：

   int n = 8;
   int ia[9] = {0, 3, 7, 9, 11, 13, 15, 16, 17};
   int ja[17] = {0, 3, 4, 1, 2, 3, 5, 2, 7, 3, 6, 4, 5, 5, 7, 6, 7};
   double a[17] = {1.0, 1.0, 2.0, 9.0, 2.0, 1.0, -3.0, 3.0, 2.0, 9.0, -5.0, 6.0, 1.0, 4.0, 1.0, 7.0, 2.0};
   
   MPI_Init(NULL, NULL);
   int size, rank;
   MPI_Comm_size(MPI_COMM_WORLD, &size);
   MPI_Comm_rank(MPI_COMM_WORLD, &rank);
   
   KmlScasolverTask* matrix_handle = NULL;
   int ierr = KmlScadssSpdInitDI(&matrix_handle, n, a, ja, ia, MPI_COMM_WORLD); //Init
   if (ierr != 0) {
       printf("\nERROR in KmlScadssSpdInitDI: %d", ierr);
   }
   ierr = KmlScadssSpdAnalyzeDI(&matrix_handle); //Analyze phase
   if (ierr != 0) {
       printf("\nERROR in KmlScadssSpdAnalyzeDI: %d", ierr);
   }
   ierr = KmlScadssSpdFactorizeDI(&matrix_handle); //Factorize phase
   if (ierr != 0) {
       printf("\nERROR in KmlScadssSpdFactorizeDI: %d", ierr);
   }
   
   int nrhs = 1;
   int ldx=n, ldb=n;
   double b[8]={4.0, 9.0, 7.0, 6.0, 9.0, 3.0, 2.0, 5.0};
   double x[8];
   
   ierr = KmlScadssSpdSolveDI(&matrix_handle, nrhs, x, ldx, b, ldb); //Solve phase
   if (ierr != 0) {
       printf("\nERROR in KmlScadssSpdSolveDI: %d", ierr);
   }
   ierr = KmlScadssSpdCleanDI(&matrix_handle); //clean
   if (ierr != 0) {
       printf("\nERROR in KmlScadssSpdcleanDI: %d", ierr);
   }
   MPI_Finalize();

2. 头文件。

   迁移前：

   #include "dmumps_c.h"

   迁移后：

   #include "kml_scadss.h"

3. 编译链接库。

   替换MUMPS相关的链接选项， 具体选项请参见《鲲鹏数学库 开发指南》中的“安装KML”章节。