// compute eigensystem of a real symmetric matrix //--------------------------------------------------------- void eig_sym(const DMat& A, DVec& ev, DMat& Q, bool bDoEVecs) //--------------------------------------------------------- { if (!A.is_square()) { umERROR("eig_sym(A)", "matrix is not square."); } int N = A.num_rows(); int LDA=N, LDVL=N, LDVR=N, ldwork=10*N, info=0; DVec work(ldwork, 0.0, OBJ_temp, "work_TMP"); Q = A; // Calculate eigenvectors in Q (optional) ev.resize(N); // Calculate eigenvalues in ev char jobV = bDoEVecs ? 'V' : 'N'; SYEV (jobV,'U', N, Q.data(), LDA, ev.data(), work.data(), ldwork, info); if (info < 0) { umERROR("eig_sym(A, Re,Im)", "Error in input argument (%d)\nNo solution computed.", -info); } else if (info > 0) { umLOG(1, "eig_sym(A, W): ...\n" "\nthe algorithm failed to converge;" "\n%d off-diagonal elements of an intermediate" "\ntridiagonal form did not converge to zero.\n", info); } }
// DPOSV uses Cholesky factorization A=U^T*U, A=L*L^T // to compute the solution to a real system of linear // equations A*X=B, where A is a square, (N,N) symmetric // positive definite matrix and X and B are (N,NRHS). // // If the system is over or under-determined, // (i.e. A is not square), then pass the problem // to the Least-squares solver (DGELSS) below. //--------------------------------------------------------- void umSOLVE_CH(const DMat& mat, const DMat& B, DMat& X) //--------------------------------------------------------- { if (!mat.ok()) {umWARNING("umSOLVE_CH()", "system is empty"); return;} if (!mat.is_square()) { umSOLVE_LS(mat, B, X); // return a least-squares solution. return; } DMat A(mat); // Work with a copy of input array. X = B; // initialize solution with rhs int rows=A.num_rows(), LDA=A.num_rows(), cols=A.num_cols(); int LDB=X.num_rows(), NRHS=X.num_cols(), info=0; assert(LDB >= rows); // enough space for solutions? // Solve the system. POSV('U', rows, NRHS, A.data(), LDA, X.data(), LDB, info); if (info < 0) { X = 0.0; umERROR("umSOLVE_CH(A,B, X)", "Error in input argument (%d)\nNo solution computed.", -info); } else if (info > 0) { X = 0.0; umERROR("umSOLVE_CH(A,B, X)", "\nINFO = %d. The leading minor of order %d of A" "\nis not positive definite, so the factorization" "\ncould not be completed. No solution computed.", info, info); } }
// DPOSV uses Cholesky factorization A=U^T*U, A=L*L^T // to compute the solution to a real system of linear // equations A*X=B, where A is a square, (N,N) symmetric // positive definite matrix and X and B are (N,NRHS). //--------------------------------------------------------- void umSOLVE_CH(const DMat& mat, const DVec& b, DVec& x) //--------------------------------------------------------- { // check args assert(mat.is_square()); // symmetric assert(b.size() >= mat.num_rows()); // is b consistent? assert(b.size() <= x.size()); // can x store solution? DMat A(mat); // work with copy of input x = b; // allocate solution vector int rows=A.num_rows(), LDA=A.num_rows(), cols=A.num_cols(); int LDB=b.size(), NRHS=1, info=0; if (rows<1) {umWARNING("umSOLVE_CH()", "system is empty"); return;} // Solve the system. POSV('U', rows, NRHS, A.data(), LDA, x.data(), LDB, info); if (info < 0) { x = 0.0; umERROR("umSOLVE_CH(A,b, x)", "Error in input argument (%d)\nNo solution computed.", -info); } else if (info > 0) { x = 0.0; umERROR("umSOLVE_CH(A,b, x)", "\nINFO = %d. The leading minor of order %d of A" "\nis not positive definite, so the factorization" "\ncould not be completed. No solution computed.", info, info); } }
// DGESV uses the LU factorization to compute solution // to a real system of linear equations, A * X = B, // where A is square (N,N) and X, B are (N,NRHS). // // If the system is over or under-determined, // (i.e. A is not square), then pass the problem // to the Least-squares solver (DGELSS) below. //--------------------------------------------------------- void umSOLVE(const DMat& mat, const DMat& B, DMat& X) //--------------------------------------------------------- { if (!mat.ok()) {umWARNING("umSOLVE()", "system is empty"); return;} if (!mat.is_square()) { umSOLVE_LS(mat, B, X); // return a least-squares solution. return; } DMat A(mat); // work with copy of input X = B; // initialize result with RHS int rows=A.num_rows(), LDA=A.num_rows(), cols=A.num_cols(); int LDB=B.num_rows(), NRHS=B.num_cols(), info=0; if (rows<1) {umWARNING("umSOLVE()", "system is empty"); return;} IVec ipiv(rows); // Solve the system. GESV(rows, NRHS, A.data(), LDA, ipiv.data(), X.data(), LDB, info); if (info < 0) { X = 0.0; umERROR("umSOLVE(A,B, X)", "Error in input argument (%d)\nNo solution computed.", -info); } else if (info > 0) { X = 0.0; umERROR("umSOLVE(A,B, X)", "\nINFO = %d. U(%d,%d) was exactly zero." "\nThe factorization has been completed, but the factor U is " "\nexactly singular, so the solution could not be computed.", info, info, info); } }
//--------------------------------------------------------- bool chol_solve(const DMat& ch, const DMat& B, DMat& X) //--------------------------------------------------------- { // Solve a set of linear systems using Cholesky-factored // symmetric positive-definite matrix, A = U^T U. if (FACT_CHOL != ch.get_factmode()) {umERROR("chol_solve(ch,B,X)", "matrix is not factored.");} int M =ch.num_rows(), lda=ch.num_rows(); int ldb=B.num_rows(), nrhs=B.num_cols(); assert(ldb == M); char uplo = 'U'; int info=0; double* ch_data = const_cast<double*>(ch.data()); X = B; // overwrite X with RHS's, then solutions POTRS (uplo, M, nrhs, ch_data, lda, X.data(), ldb, info); if (info) { umERROR("chol_solve(ch,B,X)", "dpotrs reports: info = %d", info); } return true; }
//--------------------------------------------------------- void eig(const DMat& A, DVec& Re, DMat& VL, DMat& VR, bool bL, bool bR) //--------------------------------------------------------- { // Compute eigensystem of a real general matrix // Currently NOT returning imaginary components static DMat B; if (!A.is_square()) { umERROR("eig(A)", "matrix is not square."); } int N = A.num_rows(); int LDA=N, LDVL=N, LDVR=N, ldwork=10*N, info=0; Re.resize(N); // store REAL components of eigenvalues in Re VL.resize(N,N); // storage for LEFT eigenvectors VR.resize(N,N); // storage for RIGHT eigenvectors DVec Im(N); // NOT returning imaginary components DVec work(ldwork, 0.0); // Work on a copy of A B = A; char jobL = bL ? 'V' : 'N'; // calc LEFT eigenvectors? char jobR = bR ? 'V' : 'N'; // calc RIGHT eigenvectors? GEEV (jobL,jobR, N, B.data(), LDA, Re.data(), Im.data(), VL.data(), LDVL, VR.data(), LDVR, work.data(), ldwork, info); if (info < 0) { umERROR("eig(A, Re,Im)", "Error in input argument (%d)\nNo solution computed.", -info); } else if (info > 0) { umLOG(1, "eig(A, Re,Im): ...\n" "\nThe QR algorithm failed to compute all the" "\neigenvalues, and no eigenvectors have been" "\ncomputed; elements %d+1:N of WR and WI contain" "\neigenvalues which have converged.\n", info); } #if (0) // Return (Re,Imag) parts of eigenvalues as columns of Ev Ev.resize(N,2); Ev.set_col(1, Re); Ev.set_col(2, Im); #endif #ifdef _DEBUG //##################################################### // Check for imaginary components in eigenvalues //##################################################### double im_max = Im.max_val_abs(); if (im_max > 1e-6) { umERROR("eig(A)", "imaginary components in eigenvalues."); } //##################################################### #endif }
//--------------------------------------------------------- void umAxB(const DMat& A, const DMat& B, DMat& C) //--------------------------------------------------------- { //------------------------- // C = A * B //------------------------- // A = op(A) is (M,K) // B = op(B) is (K,N) // C is (M,N) //------------------------- int M=A.num_rows(), K=A.num_cols(), N=B.num_cols(); int LDA=M, LDB=K, LDC=M; double one=1.0, zero=0.0; if (B.num_rows() != K) { umERROR("umAxB(A,B,C)", "wrong dimensions"); } C.resize(M,N); GEMM ('N','N',M,N,K, one,A.data(),LDA, B.data(),LDB, zero,C.data(),LDC); }
//--------------------------------------------------------- void Euler3D::CouetteBC3D ( const DVec& xi, const DVec& yi, const DVec& zi, const DVec& nxi, const DVec& nyi, const DVec& nzi, const IVec& tmapI, const IVec& tmapO, const IVec& tmapW, const IVec& tmapC, double ti, DMat& Qio ) //--------------------------------------------------------- { //####################################################### // FIXME: what about top and bottom of 3D annulus? //####################################################### // gmapB = concat(mapI,mapO,mapW, ...); // Check for no boundary faces if (gmapB.size() < 1) { return; } // function [Q] = CouetteBC3D(xin, yin, nxin, nyin, mapI, mapO, mapW, mapC, Q, time); // Purpose: evaluate solution for Couette flow // Couette flow (mach .2 at inner cylinder) // gamma = 1.4; int Nr = Qio.num_rows(); DVec rho,rhou,rhov,rhow,Ener; // wrap current state data (columns of Qio) rho.borrow (Nr, Qio.pCol(1)); rhou.borrow(Nr, Qio.pCol(2)); rhov.borrow(Nr, Qio.pCol(3)); rhow.borrow(Nr, Qio.pCol(4)); Ener.borrow(Nr, Qio.pCol(5)); // update boundary nodes of Qio with boundary data // pre-calculated in function precalc_bdry_data() rho (gmapB) = rhoB; rhou(gmapB) = rhouB; rhov(gmapB) = rhovB; rhow(gmapB) = rhowB; Ener(gmapB) = EnerB; }
// tex "table" output //--------------------------------------------------------- void textable ( string& capt, FILE* fid, string* titles, DMat& entries, string* form ) //--------------------------------------------------------- { int Nrows=entries.num_rows(), Ncols=entries.num_cols(), n=0,m=0; fprintf(fid, "\\begin{table} \n"); fprintf(fid, "\\caption{%s} \n", capt.c_str()); fprintf(fid, "\\begin{center} \n"); fprintf(fid, "\\begin{tabular}{|"); for (n=1; n<=Ncols; ++n) { fprintf(fid, "c|"); if (2==n) { fprintf(fid, "|"); } } fprintf(fid, "} \\hline \n "); for (n=1; n<=(Ncols-1); ++n) { fprintf(fid, "%s & ", titles[n].c_str()); } fprintf(fid, " %s \\\\ \\hline \n ", titles[Ncols].c_str()); for (m=1; m<=Nrows; ++m) { for (n=1; n<=(Ncols-1); ++n) { fprintf(fid, form[n].c_str(), entries(m,n)); fprintf(fid, " & "); } if (m<Nrows) { fprintf(fid, form[Ncols].c_str(), entries(m,Ncols)); fprintf(fid, " \\\\ \n "); } else { fprintf(fid, form[Ncols].c_str(), entries(m,Ncols)); fprintf(fid, " \\\\ \\hline \n "); } } fprintf(fid, "\\end{tabular} \n"); fprintf(fid, "\\end{center} \n"); fprintf(fid, "\\end{table} \n"); }
// DGELSS computes minimum norm solution to a real linear // least squares problem: Minimize 2-norm(| b - A*x |). // using the singular value decomposition (SVD) of A. // A is an M-by-N matrix which may be rank-deficient. //--------------------------------------------------------- void umSOLVE_LS(const DMat& mat, const DMat& B, DMat& X) //--------------------------------------------------------- { if (!mat.ok()) {umWARNING("umSOLVE_LS()", "system is empty"); return;} DMat A(mat); // work with copy of input. int rows=A.num_rows(), cols=A.num_cols(), mmn=A.min_mn(); int LDB=A.max_mn(), NRHS=B.num_cols(); if (rows!=B.num_rows()) {umERROR("umSOLVE_LS(A,B)", "Inconsistant matrix sizes.");} DVec s(mmn); // allocate array for singular values // X must be big enough to store various results. // Resize X so that its leading dimension = max(M,N), // then load the set of right hand sides. X.resize(LDB,NRHS, true, 0.0); for (int j=1; j<=NRHS; ++j) // loop across colums for (int i=1; i<=rows; ++i) // loop down rows X(i,j) = B(i,j); // RCOND is used to determine the effective rank of A. // Singular values S(i) <= RCOND*S(1) are treated as zero. // If RCOND < 0, machine precision is used instead. //double rcond = 1.0 / 1.0e16; double rcond = -1.0; // NBN: ACML does not use the work vector. int mnLo=A.min_mn(), mnHi=A.max_mn(), rank=1, info=1; int lwork = 10*mnLo + std::max(2*mnLo, std::max(mnHi, NRHS)); DVec work(lwork); // Solve the system GELSS (rows, cols, NRHS, A.data(), rows, X.data(), LDB, s.data(), rcond, rank, work.data(), lwork, info); //--------------------------------------------- // Report: //--------------------------------------------- if (info == 0) { umLOG(1, "umSOLVE_LS reports successful LS-solution." "\nRCOND = %0.6e, " "\nOptimal length of work array was %d\n", rcond, lwork); } else { if (info < 0) { X = 0.0; umERROR("umSOLVE_LS(DMat&, DMat&)", "Error in input argument (%d)\nNo solution or error bounds computed.", -info); } else if (info > 0) { X = 0.0; umERROR("umSOLVE_LS(DMat&, DMat&)", "\nThe algorithm for computing the SVD failed to converge.\n" "\n%d off-diagonal elements of an intermediate " "\nbidiagonal form did not converge to zero.\n " "\nRCOND = %0.6e, " "\nOptimal length of work array was %d.\n", info, rcond, lwork); } } }