KmlScaissCgGet?I?
获得迭代求解相关参数。
接口定义
C Interface:
int KmlScaissCgGetSII(KmlScasolverTask **handle, enum KmlSolverParam param, int *data, int nd);
int KmlScaissCgGetSIS(KmlScasolverTask **handle, enum KmlSolverParam param, float *data, int nd);
int KmlScaissCgGetDII(KmlScasolverTask **handle, enum KmlSolverParam param, int *data, int nd);
int KmlScaissCgGetDID(KmlScasolverTask **handle, enum KmlSolverParam param, double *data, int nd);
参数
参数名 |
类型 |
描述 |
输入/输出 |
---|---|---|---|
handle |
KmlScasolverTask ** |
求解器句柄,传入之前步骤的变量。 |
输入/输出 |
param |
enum KmlSolverParam |
|
输入 |
data |
|
|
输出 |
nd |
int |
data数组元素个数。 |
输入 |
返回值
返回值 |
类型 |
描述 |
---|---|---|
KMLSS_NO_ERROR |
int |
正常执行。 |
KMLSS_DATA_SIZE |
int |
参数nd不等于1。 |
KMLSS_NULL_ARGUMENT |
int |
handle,data中存在空参数。 |
KMLSS_BAD_SELECTOR |
int |
param为无效参数。 |
依赖
#include "kml_scaiss.h"
示例
C Interface:
MPI_Init(NULL, NULL); int size, rank; MPI_Comm_size(MPI_COMM_WORLD, &size);//获取总进程数 MPI_Comm_rank(MPI_COMM_WORLD, &rank);//获取当前进程标识 int mat_size = 8; int n = mat_size / size; int n_beg = n * rank; if (n * size != mat_size && rank == (size - 1)) { n = mat_size - n * rank; } int ja[26] = { 0, 3, 4, 1, 2, 3, 5, 1, 2, 7, 0, 1, 3, 6, 0, 4, 5, 1, 4, 5, 7, 3, 6, 2, 5, 7 }; double a[26] = { 1.0, 1.0, 2.0, 9.0, 2.0, 1.0, -3.0, 2.0, 3.0, 2.0, 1.0, 1.0, 9.0, -5.0, 2.0, 6.0, 1.0, -3.0, 1.0, 4.0, 1.0, -5.0, 7.0, 2.0, 1.0, 2.0 }; int ia[9] = { 0, 3, 7, 10, 14, 17, 21, 23, 26 }; int a_beg = ia[n_beg]; for (int i = n_beg; i < (n_beg + n + 1); i++) { ia[i] -= a_beg; } /* Internal KML_SCAISS structure */ KmlScasolverTask *handle; /* KML_SCAISS control parameters */ int error; /* Output error handle */ /* Create data structures */ const double *a_holder = &a[a_beg]; const int *ja_holder = &ja[a_beg]; const int *ia_holder = &ia[n_beg]; error = KmlScaissCgInitStripesDI(&handle, mat_size, 1, &n, &n_beg, &a_holder, &ja_holder, &ia_holder, MPI_COMM_WORLD); double eps = 1e-4; error = KmlScaissCgSetDID(&handle, KMLSS_THRESHOLD, &eps, 1); if (error != 0) { printf("\nERROR in KmlScaissCgSetDID with KMLSS_THRESHOLD: %d", error); return 1; } int max_iters = 2000; error = KmlScaissCgSetDII(&handle, KMLSS_MAX_ITERATION_COUNT, &max_iters, 1); if (error != 0) { printf("\nERROR in KmlScaissCgSetDII with KMLSS_MAX_ITERATION_COUNT: %d", error); return 1; } int precond = KMLSS_BJACOBI; error = KmlScaissCgSetDII(&handle, KMLSS_PRECONDITIONER_TYPE, &precond, 1); if (error != 0) { printf("\nERROR in KmlScaissCgSetDII with KMLSS_PRECONDITIONER_TYPE: %d", error); return 1; } int num_blocks = 1; error = KmlScaissCgPcSetDII(&handle, KMLSS_NUM_BLOCKS, &num_blocks, 1); if (error != 0) { printf("ERROR in KmlScaissCgPcSetDII: %d\n", error); return 1; } int subprecond = KMLSS_ICC; error = KmlScaissCgPcSetDII(&handle, KMLSS_BLOCK_METHOD, &subprecond, 1); if (error != 0) { printf("ERROR in KmlScaissCgPcSetDII: %d\n", error); return 1; } error = KmlScaissCgAnalyzeDI(&handle); if (error != 0) { printf("ERROR in KmlScaissCgAnalyzeDI: %d\n", error); return 1; } error = KmlScaissCgFactorizeDI(&handle); if (error != 0) { printf("ERROR in KmlScaissCgFactorizeDI: %d\n", error); return 1; } 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] = { 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 }; error = KmlScaissCgSolveDxDI(&handle, nrhs, &x[n_beg], ldx, &b[n_beg], ldb); if (error != 0) { printf("ERROR in KmlScaissCgSolveDI: %d\n", error); return 1; } int idata[] = {0}; error = KmlScaissCgGetDII(&handle, KMLSS_ITERATION_COUNT, idata, 1); if (error != 0) { printf("\nERROR in KmlScaissCgGetDII: %d", error); return 1; } double ddata[] = {0.0}; error = KmlScaissCgGetDID(&handle, KMLSS_TOLERANCE, ddata, 1); if (error != 0) { printf("\nERROR in KmlScaissCgGetDID: %d", error); return 1; } if (rank == 0) printf("[Solve info] Res= \t%.12g\t, iteration = \t%d\t\n", sqrt(ddata[0]), idata[0]);
运行结果(2个进程):
[Solve info] Res= 2.04475505752e-15 , iteration = 8
父主题: SCAISS-CG