示例
依赖
#include "kml_scaiss.h"
示例
C Interface:
#include <stdio.h> #include <stdlib.h> #include <kml_scaiss.h> #include "mpi.h" // USER data struct typedef struct { int n; const int *ia; const int *ja; const double *a; MPI_Comm comm; } duser; int diagonal_preconditioner(void *usr, double *x) { duser *u = (duser *)usr; int i, j; /* Apply diagonal preconditioner */ for (i = 0; i < u->n; i++) { for (j = u->ia[i]; j < u->ia[i + 1]; j++) { if (u->ja[j] == i) { x[i] /= u->a[j]; } } } return 0; } int user_spmv(void *usr, const double *x, double *y) { duser *u = (duser *)usr; int size; int rank; MPI_Comm_size(u->comm, &size); MPI_Comm_rank(u->comm, &rank); int n = 8 / size; double fullX[8] = { 0.0 }; MPI_Allgather(&x[0], n, MPI_DOUBLE, &fullX[0], n, MPI_DOUBLE, u->comm); int i, j; for (i = 0; i < u->n; i++) { double sum = 0.0; for (j = u->ia[i]; j < u->ia[i + 1]; j++) { int k = u->ja[j]; double value = u->a[j]; sum += fullX[k] * value; } y[i] = sum; } return 0; } int main(void) { /* MPI initialization */ MPI_Init(NULL, NULL); int size, rank; MPI_Comm_size(MPI_COMM_WORLD, &size); MPI_Comm_rank(MPI_COMM_WORLD, &rank); /* Matrix data (CSR, stored full matrix) | 1 * * 1 2 * * * | | * 9 2 1 * -3 * * | | * 2 3 * * * * 2 | | 1 1 * 9 * * -5 * | | 2 * * * 6 1 * * | | * -3 * * 1 4 * 1 | | * * * -5 * * 7 * | | * * 2 * * 1 * 2 | */ /* Initialize separations */ int mat_size = 8; int n = mat_size / size; int n_beg = n * rank; if (n * size != 8 && rank == (size - 1)) { n = mat_size - n * rank; } 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; } /* clang-format off */ 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 }; /* clang-format on */ /* Right-hand side vector */ double b[8] = { 4.0, 9.0, 7.0, 6.0, 9.0, 3.0, 2.0, 5.0 }; /* Solution vector */ double x[8] = { 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 }; /* Internal KML_SCAISS structure */ KmlScasolverTask *handle; /* KML_SCAISS control parameters */ int nrhs = 1; /* Number of right-hand sides */ int ldx = n, ldb = n; /*!Leading dimension of B and X */ 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); if (error != 0) { printf("ERROR in KmlScaissCgInitStripesDI: %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; } /* solve */ double x7[8] = { 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 }; error = KmlScaissCgSolveDI(&handle, nrhs, &x7[0], ldx, &b[n_beg], ldb); if (error != 0) { printf("ERROR in KmlScaissCgSolveDI: %d\n", error); return 1; } /* Print the solution */ if (rank == 0) { printf("solve, x:\n"); for (int i = 0; i < n; i++) { printf("%lf\n", x7[i]); } } /* solveDx */ double x0[8] = { 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 }; error = KmlScaissCgSolveDxDI(&handle, nrhs, &x0[n_beg], ldx, &b[n_beg], ldb); if (error != 0) { printf("ERROR in KmlScaissCgSolveDI: %d\n", error); return 1; } /* Print the solution */ if (rank == 0) { printf("solveDx, x:\n"); for (int i = 0; i < n; i++) { printf("%lf\n", x0[i]); } } /* L1 norm */ int NormType = KMLSS_L1; error = KmlScaissCgSetDII(&handle, KMLSS_VECTOR_NORM_TYPE, &NormType, 1); if (error != 0) { printf("ERROR in KmlScaissCgSetDII: %d\n", error); return 1; } /* Solve */ error = KmlScaissCgSolveDI(&handle, nrhs, &x[0], ldx, &b[n_beg], ldb); if (error != 0) { printf("ERROR in KmlScaissCgSolveDI: %d\n", error); return 1; } /* Print the solution */ if (rank == 0) { printf("L1 norm, x:\n"); for (int i = 0; i < mat_size; i++) { printf("%lf\n", x[i]); } } /* SolveDx */ double x6[8] = { 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 }; error = KmlScaissCgSolveDxDI(&handle, nrhs, &x6[n_beg], ldx, &b[n_beg], ldb); if (error != 0) { printf("ERROR in KmlScaissCgSolveDI: %d\n", error); return 1; } /* Print the solution */ if (rank == 0) { printf("L2 norm, x:\n"); for (int i = 0; i < n; i++) { printf("%lf\n", x6[i]); } } /* L2 norm */ NormType = KMLSS_L2; error = KmlScaissCgSetDII(&handle, KMLSS_VECTOR_NORM_TYPE, &NormType, 1); if (error != 0) { printf("ERROR in KmlScaissCgSetDII: %d\n", error); return 1; } /* Solve */ double x2[8] = { 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 }; error = KmlScaissCgSolveDI(&handle, nrhs, &x2[0], ldx, &b[n_beg], ldb); if (error != 0) { printf("ERROR in KmlScaissCgSolveDI: %d\n", error); return 1; } /* Print the solution */ if (rank == 0) { printf("L2 norm, x:\n"); for (int i = 0; i < mat_size; i++) { printf("%lf\n", x2[i]); } } /* abs residual */ double res = 1e-10; error = KmlScaissCgSetDID(&handle, KMLSS_ABS_TOLERANCE, &res, 1); if (error != 0) { printf("ERROR in KmlScaissCgSetDIA: %d\n", error); return 1; } /* Solve */ double x3[8] = { 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 }; error = KmlScaissCgSolveDI(&handle, nrhs, &x3[0], ldx, &b[n_beg], ldb); if (error != 0) { printf("ERROR in KmlScaissCgSolveDI: %d\n", error); return 1; } /* Print the solution */ if (rank == 0) { printf("abs residual, x:\n"); for (int i = 0; i < mat_size; i++) { printf("%lf\n", x3[i]); } } /* relative residual */ res = 1e-10; error = KmlScaissCgSetDID(&handle, KMLSS_THRESHOLD, &res, 1); if (error != 0) { printf("ERROR in KmlScaissCgSetDIA: %d\n", error); return 1; } /* Solve */ double x4[8] = { 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 }; error = KmlScaissCgSolveDI(&handle, nrhs, &x4[0], ldx, &b[n_beg], ldb); if (error != 0) { printf("ERROR in KmlScaissCgSolveDI: %d\n", error); return 1; } /* Print the solution */ if (rank == 0) { printf("relative residual, x:\n"); for (int i = 0; i < mat_size; i++) { printf("%lf\n", x4[i]); } } /* Second call with preconditioner */ double x5[8] = { 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 }; duser prea; prea.n = n; prea.ia = &ia[n_beg]; prea.ja = &ja[a_beg]; prea.a = &a[a_beg]; /* Set user preconditioner */ error = KmlScaissCgSetUserPreconditionerDI(&handle, &prea, &diagonal_preconditioner); if (error != 0) { printf("ERROR in KmlScaissCgSetUserPreconditionerDI: %d\n", error); return 1; } /* Solve */ error = KmlScaissCgSolveDI(&handle, nrhs, &x5[0], ldx, &b[n_beg], ldb); if (error != 0) { printf("ERROR in KmlScaissCgSolveDI: %d\n", error); return 1; } /* Finalize and Clean-up */ error = KmlScaissCgCleanDI(&handle); if (error != 0) { printf("ERROR in KmlScaissCgCleanDI: %d\n", error); return 1; } /* Print the solution */ if (rank == 0) { printf("user preconditioner, x:\n"); for (int i = 0; i < mat_size; i++) { printf("%lf\n", x5[i]); } } /* Second call with user spmv */ KmlScasolverTask *handle2; double x8[8] = { 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 }; duser prea2; prea2.n = n; prea2.ia = &ia[n_beg]; prea2.ja = &ja[a_beg]; prea2.a = &a[a_beg]; prea2.comm = MPI_COMM_WORLD; error = KmlScaissCgInitWithoutMatDI(&handle2, 1, &n, MPI_COMM_WORLD); if (error != 0) { printf("ERROR in KmlScaissCgInitWithouMatDI: %d\n", error); return 1; } /* Set user spmv */ error = KmlScaissCgSetUserSpmvDI(&handle2, &prea2, &user_spmv); if (error != 0) { printf("ERROR in KmlScaissCgSetUserSpmvDI: %d\n", error); return 1; } /* Solve */ error = KmlScaissCgSolveDxDI(&handle2, nrhs, &x8[n_beg], ldx, &b[n_beg], ldb); if (error != 0) { printf("ERROR in KmlScaissCgSolveDI: %d\n", error); return 1; } /* Finalize and Clean-up */ error = KmlScaissCgCleanDI(&handle2); if (error != 0) { printf("ERROR in KmlScaissCgCleanDI: %d\n", error); return 1; } /* Print the solution */ if (rank == 0) { printf("user spmv, x:\n"); for (int i = 0; i < n; i++) { printf("%lf\n", x8[i]); } } MPI_Finalize(); return 0; }
父主题: SCAISS-CG