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-rw-r--r--src/solve.c636
1 files changed, 636 insertions, 0 deletions
diff --git a/src/solve.c b/src/solve.c
new file mode 100644
index 0000000..0bd56e2
--- /dev/null
+++ b/src/solve.c
@@ -0,0 +1,636 @@
+
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <cblas.h>
+#include <lapacke.h>
+
+#include <cl.h>
+#include <clBLAS.h>
+
+#include "qms.h"
+
+static int construct_matrix(MaximalSlicingContext *ms)
+{
+ double *mat = ms->mat;
+ int idx_coeff, idx_grid;
+
+#pragma omp parallel for
+ for (idx_coeff = 0; idx_coeff < ms->nb_coeffs; idx_coeff++)
+ for (idx_grid = 0; idx_grid < ms->nb_colloc_points; idx_grid++) {
+ const int idx = idx_grid + ms->nb_colloc_points * idx_coeff;
+
+ mat[idx] = ms->eq_coeff_00[idx_grid] * ms->basis_val_00[idx] +
+ ms->eq_coeff_10[idx_grid] * ms->basis_val_10[idx] +
+ ms->eq_coeff_01[idx_grid] * ms->basis_val_01[idx] +
+ ms->eq_coeff_11[idx_grid] * ms->basis_val_11[idx] +
+ ms->eq_coeff_20[idx_grid] * ms->basis_val_20[idx] +
+ ms->eq_coeff_02[idx_grid] * ms->basis_val_02[idx];
+ }
+
+ return 0;
+}
+
+/* interpolate the cactus gridfunctions onto the pseudospectral grid */
+static int interp_geometry(MaximalSlicingContext *ms)
+{
+ int ret;
+
+ ret = CCTK_InterpGridArrays(ms->gh, 3, ms->interp_operator, ms->interp_params,
+ ms->coord_system, ms->nb_colloc_points, CCTK_VARIABLE_REAL,
+ (const void * const *)ms->interp_coords, ARRAY_ELEMS(ms->interp_vars_indices), ms->interp_vars_indices,
+ ARRAY_ELEMS(ms->interp_values), ms->interp_value_codes, (void * const *)ms->interp_values_prefilter);
+ if (ret < 0)
+ CCTK_WARN(0, "Error interpolating");
+
+ CCTK_TimerStart("MaximalSlicingAxi_filter_input");
+ for (int i = 0; i < ARRAY_ELEMS(ms->interp_values); i++) {
+ cblas_dgemv(CblasColMajor, CblasNoTrans, ms->nb_colloc_points, ms->nb_colloc_points, 1.0,
+ ms->input_filter, ms->nb_colloc_points, ms->interp_values_prefilter[i], 1, 0.0,
+ ms->interp_values[i], 1);
+ }
+ CCTK_TimerStop("MaximalSlicingAxi_filter_input");
+
+ return 0;
+}
+
+static int calc_eq_coeffs(MaximalSlicingContext *ms, double *prhs_max)
+{
+ double rhs_max = 0.0;
+//#pragma omp parallel for schedule(dynamic, ms->nb_colloc_points_x) reduction(max : rhs_max)
+ for (int i = 0; i < ms->nb_colloc_points; i++) {
+ const double x = ms->interp_coords[0][i];
+ const double z = ms->interp_coords[2][i];
+ const int zaxis = x <= EPS;
+
+ double Am[3][3], K[3][3], Km[3][3], Ku[3][3], gtu[3][3];
+ double k2, kij_dij_alpha, k_kdot, k3;
+
+ const double gtxx = ms->interp_values[I_GTXX][i];
+ const double gtyy = ms->interp_values[I_GTYY][i];
+ const double gtzz = ms->interp_values[I_GTZZ][i];
+ const double gtxy = ms->interp_values[I_GTXY][i];
+ const double gtxz = ms->interp_values[I_GTXZ][i];
+ const double gtyz = ms->interp_values[I_GTYZ][i];
+
+ const double gt[3][3] = {{ gtxx, gtxy, gtxz },
+ { gtxy, gtyy, gtyz },
+ { gtxz, gtyz, gtzz }};
+
+ const double Atxx = ms->interp_values[I_ATXX][i];
+ const double Atyy = ms->interp_values[I_ATYY][i];
+ const double Atzz = ms->interp_values[I_ATZZ][i];
+ const double Atxy = ms->interp_values[I_ATXY][i];
+ const double Atxz = ms->interp_values[I_ATXZ][i];
+ const double Atyz = ms->interp_values[I_ATYZ][i];
+
+ const double phi = ms->interp_values[I_PHI][i];
+
+ const double phidot = ms->interp_values[I_PHIDOT][i];
+ const double phidot_dx = ms->interp_values[I_PHIDOT_DX][i];
+ const double phidot_dz = ms->interp_values[I_PHIDOT_DZ][i];
+
+ const double At[3][3] = {{ Atxx, Atxy, Atxz },
+ { Atxy, Atyy, Atyz },
+ { Atxz, Atyz, Atzz }};
+
+ const double trK = ms->interp_values[I_K][i];
+ const double kdot_xx = ms->interp_values[I_KDOT_XX][i];
+ const double kdot_yy = ms->interp_values[I_KDOT_YY][i];
+ const double kdot_zz = ms->interp_values[I_KDOT_ZZ][i];
+ const double kdot_xy = ms->interp_values[I_KDOT_XY][i];
+ const double kdot_xz = ms->interp_values[I_KDOT_XZ][i];
+ const double kdot_yz = ms->interp_values[I_KDOT_YZ][i];
+
+ const double kdot[3][3] = {{ kdot_xx, kdot_xy, kdot_xz },
+ { kdot_xy, kdot_yy, kdot_yz },
+ { kdot_xz, kdot_yz, kdot_zz }};
+
+ const double alpha = ms->interp_values[I_ALPHA][i];
+ const double dx_alpha = ms->interp_values[I_ALPHA_DX][i];
+ const double dz_alpha = ms->interp_values[I_ALPHA_DZ][i];
+ const double dxx_alpha = ms->interp_values[I_ALPHA_DXX][i];
+ const double dzz_alpha = ms->interp_values[I_ALPHA_DZZ][i];
+ const double dxz_alpha = ms->interp_values[I_ALPHA_DXZ][i];
+
+ const double dij_alpha[3][3] = {{ dxx_alpha, 0, dxz_alpha },
+ { 0, zaxis ? dxx_alpha : dx_alpha / x, 0 },
+ { dxz_alpha, 0, dzz_alpha }};
+
+ const double Xtx = ms->interp_values[I_XTX][i];
+ const double Xtz = ms->interp_values[I_XTZ][i];
+
+ const double Xtdot_x = ms->interp_values[I_XTDOT_X][i];
+ const double Xtdot_z = ms->interp_values[I_XTDOT_Z][i];
+
+ const double det = gtxx * gtyy * gtzz + 2 * gtxy * gtyz * gtxz - gtzz * SQR(gtxy) - SQR(gtxz) * gtyy - gtxx * SQR(gtyz);
+
+ // \tilde{γ}^{ij}
+ gtu[0][0] = (gtyy * gtzz - SQR(gtyz)) / det;
+ gtu[1][1] = (gtxx * gtzz - SQR(gtxz)) / det;
+ gtu[2][2] = (gtxx * gtyy - SQR(gtxy)) / det;
+ gtu[0][1] = -(gtxy * gtzz - gtyz * gtxz) / det;
+ gtu[0][2] = (gtxy * gtyz - gtyy * gtxz) / det;
+ gtu[1][2] = -(gtxx * gtyz - gtxy * gtxz) / det;
+ gtu[1][0] = gtu[0][1];
+ gtu[2][0] = gtu[0][2];
+ gtu[2][1] = gtu[1][2];
+
+ // K_{ij}
+ for (int j = 0; j < 3; j++)
+ for (int k = 0; k < 3; k++)
+ K[j][k] = At[j][k] / SQR(phi) + gt[j][k] * trK;
+
+ for (int j = 0; j < 3; j++)
+ for (int k = 0; k < 3; k++) {
+ double val = 0.0;
+ for (int l = 0; l < 3; l++)
+ val += SQR(phi) * gtu[j][l] * K[l][k];
+ Km[j][k] = val;
+ }
+
+ // K^{ij}
+ for (int j = 0; j < 3; j++)
+ for (int k = 0; k < 3; k++) {
+ double val = 0.0;
+ for (int l = 0; l < 3; l++)
+ val += SQR(phi) * gtu[j][l] * Km[k][l];
+ Ku[j][k] = val;
+ }
+
+ // \tilde{A}_{i}^j
+ for (int j = 0; j < 3; j++)
+ for (int k = 0; k < 3; k++) {
+ double val = 0.0;
+ for (int l = 0; l < 3; l++)
+ val += gtu[j][l] * At[l][k];
+ Am[j][k] = val;
+ }
+
+ kij_dij_alpha = 0.0;
+ for (int j = 0; j < 3; j++)
+ for (int k = 0; k < 3; k++)
+ kij_dij_alpha += Ku[j][k] * dij_alpha[j][k];
+
+ k_kdot = 0.0;
+ for (int j = 0; j < 3; j++)
+ for (int k = 0; k < 3; k++)
+ k_kdot += kdot[j][k] * Ku[j][k];
+
+ k3 = 0.0;
+ for (int j = 0; j < 3; j++)
+ for (int k = 0; k < 3; k++) {
+ double val = 0.0;
+ for (int l = 0; l < 3; l++)
+ val += Km[k][l] * Ku[l][j];
+ k3 += val * K[j][k];
+ }
+
+ // K_{ij} K^{ij}
+ k2 = 0.0;
+ for (int j = 0; j < 3; j++)
+ for (int k = 0; k < 3; k++)
+ k2 += Km[j][k] * Km[k][j];
+
+ {
+ const double gtuxx = gtu[0][0];
+ const double gtuyy = gtu[1][1];
+ const double gtuzz = gtu[2][2];
+ const double gtuxz = gtu[0][2];
+
+ const double phi_dx = ms->interp_values[I_PHI_DX][i];
+ const double phi_dz = ms->interp_values[I_PHI_DZ][i];
+
+ const double Xtx = ms->interp_values[I_XTX][i];
+ const double Xtz = ms->interp_values[I_XTZ][i];
+
+ //const double k2 = a2 + SQR(trK) / 3.;
+
+ const double trk_dx = ms->interp_values[I_K_DX][i];
+ const double trk_dz = ms->interp_values[I_K_DZ][i];
+
+ const double betax = ms->interp_values[I_BETAX][i];
+ const double betaz = ms->interp_values[I_BETAZ][i];
+
+ const double Xx = SQR(phi) * (Xtx + (phi_dx * gtuxx + phi_dz * gtuxz) / phi);
+ const double Xz = SQR(phi) * (Xtz + (phi_dx * gtuxz + phi_dz * gtuzz) / phi);
+
+ const double Xdot_x = 2 * phi * phidot * Xtx + SQR(phi) * Xtdot_x + phi * (phidot_dx * gtuxx + phidot_dz * gtuxz) -
+ phidot * (phi_dx * gtuxx + phi_dz * gtuxz) + 2 * alpha * (phi_dx * Ku[0][0] + phi_dz * Ku[0][2]) / phi;
+ const double Xdot_z = 2 * phi * phidot * Xtz + SQR(phi) * Xtdot_z + phi * (phidot_dz * gtuzz + phidot_dx * gtuxz) -
+ phidot * (phi_dz * gtuzz + phi_dx * gtuxz) + 2 * alpha * (phi_dz * Ku[2][2] + phi_dx * Ku[0][2]) / phi;
+
+ ms->eq_coeff_20[i] = SQR(phi) * (gtuxx + ((x <= EPS) ? gtuyy : 0.0));
+ ms->eq_coeff_02[i] = SQR(phi) * gtuzz;
+ ms->eq_coeff_11[i] = SQR(phi) * gtuxz * 2;
+ ms->eq_coeff_10[i] = -Xx + ((x > EPS) ? SQR(phi) * gtuyy / x : 0.0);
+ ms->eq_coeff_01[i] = -Xz;
+ ms->eq_coeff_00[i] = -k2;
+
+ ms->rhs[i] = -2 * alpha * kij_dij_alpha + Xdot_x * dx_alpha + Xdot_z * dz_alpha +
+ 2 * (k_kdot + 2 * alpha * k3) * alpha;
+
+ rhs_max = MAX(rhs_max, fabs(ms->rhs[i]));
+ }
+ }
+
+ *prhs_max = rhs_max;
+
+ return 0;
+}
+
+// based on the wikipedia article
+// and http://www.netlib.org/templates/matlab/bicgstab.m
+static int solve_bicgstab(BiCGSTABContext *ctx, const int N,
+ double *mat, double *rhs, double *x)
+{
+ const double rhs_norm = cblas_dnrm2(N, rhs, 1);
+
+ double rho, rho_prev = 1.0;
+ double omega = 1.0;
+ double alpha = 1.0;
+
+ double err;
+ int i;
+
+ double *k = ctx->k;
+ double *p = ctx->p, *v = ctx->v, *y = ctx->y, *z = ctx->z, *t = ctx->t;
+ double *res = ctx->res, *res0 = ctx->res0;
+
+ // initialize the residual
+ memcpy(res, rhs, N * sizeof(*res));
+ cblas_dgemv(CblasColMajor, CblasNoTrans, N, N, -1.0,
+ mat, N, x, 1, 1.0, res, 1);
+
+ memcpy(res0, res, N * sizeof(*res0));
+ memcpy(p, res, N * sizeof(*p));
+
+#define MAXITER 16
+#define TOL (1e-15)
+ for (i = 0; i < MAXITER; i++) {
+ rho = cblas_ddot(N, res, 1, res0, 1);
+
+ if (i) {
+ double beta = (rho / rho_prev) * (alpha / omega);
+
+ cblas_daxpy(N, -omega, v, 1, p, 1);
+ cblas_dscal(N, beta, p, 1);
+ cblas_daxpy(N, 1, res, 1, p, 1);
+ }
+
+ cblas_dgemv(CblasColMajor, CblasNoTrans, N, N, 1.0,
+ k, N, p, 1, 0.0, y, 1);
+
+ cblas_dgemv(CblasColMajor, CblasNoTrans, N, N, 1.0,
+ mat, N, y, 1, 0.0, v, 1);
+
+ alpha = rho / cblas_ddot(N, res0, 1, v, 1);
+
+ cblas_daxpy(N, -alpha, v, 1, res, 1);
+
+ cblas_dgemv(CblasColMajor, CblasNoTrans, N, N, 1.0,
+ k, N, res, 1, 0.0, z, 1);
+ cblas_dgemv(CblasColMajor, CblasNoTrans, N, N, 1.0,
+ mat, N, z, 1, 0.0, t, 1);
+
+ omega = cblas_ddot(N, t, 1, res, 1) / cblas_ddot(N, t, 1, t, 1);
+
+ cblas_daxpy(N, alpha, y, 1, x, 1);
+ cblas_daxpy(N, omega, z, 1, x, 1);
+
+ cblas_daxpy(N, -omega, t, 1, res, 1);
+
+ err = cblas_dnrm2(N, res, 1) / rhs_norm;
+ if (err < TOL)
+ break;
+
+ rho_prev = rho;
+ }
+ if (i == MAXITER)
+ return -1;
+
+ return i;
+}
+
+static int solve_bicgstab_cl(BiCGSTABContext *ctx, cl_command_queue cl_q,
+ const int N, double *mat, double *rhs, cl_mem ocl_x)
+{
+ const double rhs_norm = cblas_dnrm2(N, rhs, 1);
+
+ double rho, rho_prev = 1.0;
+ double omega[2] = { 1.0 };
+ double alpha = 1.0;
+
+ double err;
+ int i;
+
+ cl_event events[8];
+
+ // the matrix, rhs, k and x are assumed to be already uploaded
+ clEnqueueWriteBuffer(cl_q, ctx->cl_res, 0, 0, N * sizeof(double), rhs, 0, NULL, &events[0]);
+ clEnqueueWriteBuffer(cl_q, ctx->cl_mat, 0, 0, N * N * sizeof(double), mat, 0, NULL, &events[1]);
+
+ // initialize the residual
+ clblasDgemv(CblasColMajor, CblasNoTrans, N, N, -1.0,
+ ctx->cl_mat, 0, N, ocl_x, 0, 1, 1.0, ctx->cl_res, 0, 1,
+ 1, &cl_q, 2, events, &events[2]);
+ clEnqueueCopyBuffer(cl_q, ctx->cl_res, ctx->cl_res0, 0, 0, N * sizeof(double),
+ 1, &events[2], &events[3]);
+ clEnqueueCopyBuffer(cl_q, ctx->cl_res, ctx->cl_p, 0, 0, N * sizeof(double),
+ 1, &events[2], &events[4]);
+
+ clWaitForEvents(5, events);
+ // BARRIER
+
+#define MAXITER 16
+#define TOL (1e-15)
+ for (i = 0; i < MAXITER; i++) {
+ clblasDdot(N, ctx->cl_rho, 0, ctx->cl_res, 0, 1, ctx->cl_res0, 0, 1,
+ ctx->cl_tmp, 1, &cl_q, 0, NULL, &events[0]);
+ clEnqueueReadBuffer(cl_q, ctx->cl_rho, 1, 0, sizeof(double), &rho,
+ 1, &events[0], NULL);
+ // BARRIER
+
+ if (i) {
+ double beta = (rho / rho_prev) * (alpha / omega[0]);
+
+ clblasDaxpy(N, -omega[0], ctx->cl_v, 0, 1, ctx->cl_p, 0, 1,
+ 1, &cl_q, 0, NULL, &events[0]);
+ clblasDscal(N, beta, ctx->cl_p, 0, 1,
+ 1, &cl_q, 1, &events[0], &events[1]);
+ clblasDaxpy(N, 1, ctx->cl_res, 0, 1, ctx->cl_p, 0, 1,
+ 1, &cl_q, 1, &events[1], &events[0]);
+ clWaitForEvents(1, &events[0]);
+ // BARRIER
+ }
+
+ clblasDgemv(CblasColMajor, CblasNoTrans, N, N, 1.0,
+ ctx->cl_k, 0, N, ctx->cl_p, 0, 1, 0.0, ctx->cl_y, 0, 1,
+ 1, &cl_q, 0, NULL, &events[0]);
+
+ clblasDgemv(CblasColMajor, CblasNoTrans, N, N, 1.0,
+ ctx->cl_mat, 0, N, ctx->cl_y, 0, 1, 0.0, ctx->cl_v, 0, 1,
+ 1, &cl_q, 1, &events[0], &events[1]);
+
+ clblasDdot(N, ctx->cl_alpha, 0, ctx->cl_res0, 0, 1, ctx->cl_v, 0, 1,
+ ctx->cl_tmp, 1, &cl_q, 1, &events[1], &events[0]);
+ clEnqueueReadBuffer(cl_q, ctx->cl_alpha, 1, 0, sizeof(double), &alpha,
+ 1, &events[0], NULL);
+ // BARRIER
+
+ alpha = rho / alpha;
+
+ clblasDaxpy(N, -alpha, ctx->cl_v, 0, 1, ctx->cl_res, 0, 1,
+ 1, &cl_q, 0, NULL, &events[0]);
+
+ clblasDgemv(CblasColMajor, CblasNoTrans, N, N, 1.0,
+ ctx->cl_k, 0, N, ctx->cl_res, 0, 1, 0.0, ctx->cl_z, 0, 1,
+ 1, &cl_q, 1, &events[0], &events[1]);
+ clblasDgemv(CblasColMajor, CblasNoTrans, N, N, 1.0,
+ ctx->cl_mat, 0, N, ctx->cl_z, 0, 1, 0.0, ctx->cl_t, 0, 1,
+ 1, &cl_q, 1, &events[1], &events[0]);
+
+ clblasDdot(N, ctx->cl_omega, 0, ctx->cl_t, 0, 1, ctx->cl_res, 0, 1,
+ ctx->cl_tmp, 1, &cl_q, 1, &events[0], &events[1]);
+ clblasDdot(N, ctx->cl_omega, 1, ctx->cl_t, 0, 1, ctx->cl_t, 0, 1,
+ ctx->cl_tmp1, 1, &cl_q, 1, &events[0], &events[2]);
+
+ clEnqueueReadBuffer(cl_q, ctx->cl_omega, 1, 0, sizeof(omega), omega,
+ 2, &events[1], NULL);
+ // BARRIER
+
+ omega[0] /= omega[1];
+
+ clblasDaxpy(N, alpha, ctx->cl_y, 0, 1, ocl_x, 0, 1,
+ 1, &cl_q, 0, NULL, &events[0]);
+ clblasDaxpy(N, omega[0], ctx->cl_z, 0, 1, ocl_x, 0, 1,
+ 1, &cl_q, 1, &events[0], &events[1]);
+
+ clblasDaxpy(N, -omega[0], ctx->cl_t, 0, 1, ctx->cl_res, 0, 1,
+ 1, &cl_q, 0, NULL, &events[0]);
+ clblasDnrm2(N, ctx->cl_tmp, 0, ctx->cl_res, 0, 1, ctx->cl_tmp1,
+ 1, &cl_q, 1, &events[0], &events[2]);
+ clEnqueueReadBuffer(cl_q, ctx->cl_tmp, 1, 0, sizeof(double), &err,
+ 1, &events[2], NULL);
+ clWaitForEvents(1, &events[1]);
+ // BARRIER
+
+ if (err < TOL)
+ break;
+
+ rho_prev = rho;
+ }
+ if (i == MAXITER)
+ return -1;
+
+ return i;
+}
+
+static int lu_invert(const int N, double *mat, double *rhs, int *ipiv)
+{
+ char equed = 'N';
+ double cond, ferr, berr, rpivot;
+
+ double *mat_f, *x;
+ int ret = 0;
+#if 1
+ LAPACKE_dgesv(LAPACK_COL_MAJOR, N, 1,
+ mat, N, ipiv, rhs, N);
+ LAPACKE_dgetri(LAPACK_COL_MAJOR, N, mat, N, ipiv);
+#else
+ mat_f = malloc(SQR(N) * sizeof(*mat_f));
+ x = malloc(N * sizeof(*x));
+
+ //{
+ // int i, j;
+ // for (i = 0; i < N; i++) {
+ // for (j = 0; j < N; j++)
+ // fprintf(stderr, "%+#010.8g\t", mat[i + j * N]);
+ // fprintf(stderr, "\n");
+ // }
+ //}
+ //{
+ // double *mat_copy = malloc(SQR(N) * sizeof(double));
+ // double *svd = malloc(N * sizeof(double));
+ // double *rhs_copy = malloc(N * sizeof(double));
+ // int rank;
+
+ // memcpy(mat_copy, mat, SQR(N) * sizeof(double));
+ // memcpy(rhs_copy, rhs, N * sizeof(double));
+
+ // LAPACKE_dgelsd(LAPACK_COL_MAJOR, N, N, 1, mat_copy, N, rhs_copy, N,
+ // svd, 1e-13, &rank);
+
+ // free(mat_copy);
+ // for (int i = 0; i < N; i++) {
+ // if (i > 5 && i < N - 5)
+ // continue;
+
+ // fprintf(stderr, "%g\t", svd[i]);
+ // }
+ // fprintf(stderr, "\n rank %d\n", rank);
+ // free(svd);
+ // free(rhs_copy);
+
+ // if (rank < N)
+ // ret = 1;
+ //}
+
+ //LAPACKE_dgesv(LAPACK_COL_MAJOR, N, 1,
+ // mat, N, ipiv, rhs, N);
+ LAPACKE_dgesvx(LAPACK_COL_MAJOR, 'N', 'N', N, 1,
+ mat, N, mat_f, N, ipiv, &equed, NULL, NULL,
+ rhs, N, x, N, &cond, &ferr, &berr, &rpivot);
+ LAPACKE_dgetri(LAPACK_COL_MAJOR, N, mat_f, N, ipiv);
+ memcpy(rhs, x, N * sizeof(double));
+ memcpy(mat, mat_f, SQR(N) * sizeof(double));
+
+ fprintf(stderr, "LU factorization solution to a %zdx%zd matrix: "
+ "condition number %16.16g; forward error %16.16g backward error %16.16g\n",
+ N, N, cond, ferr, berr);
+
+ free(mat_f);
+ free(x);
+#endif
+
+ return ret;
+}
+
+/*
+ * Solve the equation
+ * D²α - KᵢⱼKⁱʲα = -K
+ * for the coefficients of spectral approximation of α:
+ * α(ρ, z) = 1 + ΣaᵢⱼTᵢ(ρ)Tⱼ(z)
+ * where i = { 0, ... , ms->nb_coeffs_x };
+ * j = { 0, ... , ms->nb_coeffs_z };
+ * Tᵢ(x) are defined by ms->basis.
+ */
+int qms_maximal_solve(MaximalSlicingContext *ms)
+{
+ const int N = ms->nb_coeffs;
+ double rhs_max;
+ int64_t start;
+
+ int ret = 0;
+
+ /* interpolate the metric values and construct the quantities we'll need */
+ CCTK_TimerStart("MaximalSlicingAxi_interp_geometry");
+ start = gettime();
+ ret = interp_geometry(ms);
+ ms->interp_geometry_time += gettime() - start;
+ ms->interp_geometry_count++;
+ CCTK_TimerStop("MaximalSlicingAxi_interp_geometry");
+ if (ret < 0)
+ return ret;
+
+ CCTK_TimerStart("MaximalSlicingAxi_calc_eq_coeffs");
+ start = gettime();
+ ret = calc_eq_coeffs(ms, &rhs_max);
+ ms->calc_eq_coeffs_time += gettime() - start;
+ ms->calc_eq_coeffs_count++;
+ CCTK_TimerStop("MaximalSlicingAxi_calc_eq_coeffs");
+ if (ret < 0)
+ return ret;
+
+ /* fill the matrix */
+ CCTK_TimerStart("MaximalSlicingAxi_construct_matrix");
+ start = gettime();
+ ret = construct_matrix(ms);
+ ms->construct_matrix_time += gettime() - start;
+ ms->construct_matrix_count++;
+ CCTK_TimerStop("MaximalSlicingAxi_construct_matrix");
+ if (ret < 0)
+ return ret;
+
+#if 1
+ if (rhs_max < EPS) {
+ fprintf(stderr, "zero rhs\n");
+ memset(ms->coeffs, 0, sizeof(*ms->coeffs) * ms->nb_coeffs);
+ if (ms->cl_queue) {
+ clEnqueueWriteBuffer(ms->cl_queue, ms->ocl_coeffs, 1, 0, N * sizeof(double),
+ ms->coeffs, 0, NULL, NULL);
+ }
+ return 0;
+ }
+#endif
+
+ /* solve for the coeffs */
+ if (ms->steps_since_inverse < 1024) {
+ BiCGSTABContext *b = &ms->bicgstab;
+ int64_t start = gettime();
+
+ CCTK_TimerStart("MaximalSlicingAxi_solve_BiCGSTAB");
+ if (ms->cl_queue) {
+ ret = solve_bicgstab_cl(b, ms->cl_queue, ms->nb_coeffs, ms->mat, ms->rhs, ms->ocl_coeffs);
+ clEnqueueReadBuffer(ms->cl_queue, ms->ocl_coeffs, 1, 0, sizeof(double) * N,
+ ms->coeffs, 0, NULL, NULL);
+ } else
+ ret = solve_bicgstab(b, ms->nb_coeffs, ms->mat, ms->rhs, ms->coeffs);
+ CCTK_TimerStop("MaximalSlicingAxi_solve_BiCGSTAB");
+
+ if (ret >= 0) {
+ ms->cg_time_total += gettime() - start;
+ ms->cg_solve_count++;
+ ms->cg_iter_count += ret + 1;
+ ms->steps_since_inverse++;
+
+#if 0
+ {
+ double min, max;
+ gsl_vector_memcpy(b->y, ms->rhs);
+ cblas_dgemv(CblasColMajor, CblasNoTrans, ms->mat->size1, ms->mat->size2, -1.0,
+ ms->mat->data, ms->mat->tda, ms->coeffs->data, 1, 1.0, b->y->data, 1);
+ gsl_vector_minmax(b->y, &min, &max);
+ if (fabs(min) > 1e-11 || fabs(max) > 1e-11)
+ abort();
+ }
+#endif
+ }
+ } else
+ ret = -1;
+
+ if (ret < 0) {
+ double *tmpv;
+ double *tmpm;
+ int64_t start;
+
+ CCTK_TimerStart("MaximalSlicingAxi_solve_LU");
+ start = gettime();
+
+ ret = lu_invert(ms->nb_coeffs, ms->mat, ms->rhs, ms->ipiv);
+ ms->lu_solves_time += gettime() - start;
+ ms->lu_solves_count++;
+ CCTK_TimerStop("MaximalSlicingAxi_solve_LU");
+
+ tmpv = ms->coeffs;
+ ms->coeffs = ms->rhs;
+ ms->rhs = tmpv;
+
+ tmpm = ms->mat;
+ ms->mat = ms->bicgstab.k;
+ ms->bicgstab.k = tmpm;
+
+ if (ret == 1) {
+ memset(ms->coeffs, 0, sizeof(*ms->coeffs) * ms->nb_coeffs);
+ ms->coeffs[0] = 1.0;
+ }
+
+ if (ms->cl_queue) {
+ cl_event events[2];
+ clEnqueueWriteBuffer(ms->cl_queue, ms->bicgstab.cl_k, 0, 0, N * N * sizeof(double),
+ ms->bicgstab.k, 0, NULL, &events[0]);
+ clEnqueueWriteBuffer(ms->cl_queue, ms->ocl_coeffs, 0, 0, N * sizeof(double),
+ ms->coeffs, 0, NULL, &events[1]);
+ clWaitForEvents(2, events);
+ }
+
+ ms->steps_since_inverse = 0;
+ }
+
+ for (int i = 0; i < N; i++)
+ ms->coeffs[i] *= ms->coeff_scale[i];
+
+ return ret;
+}