Section 3: library functions
dlamchf77.f – SynopsisFunctions/SubroutinesDOUBLE PRECISION function dlamch (CMACH) DLAMCHF77 deprecated subroutine dlamc1 (BETA, T, RND, IEEE1) DLAMC1 subroutine dlamc2 (BETA, T, RND, EPS, EMIN, RMIN, EMAX, RMAX) DLAMC2 DOUBLE PRECISION function dlamc3 (A, B) DLAMC3 subroutine dlamc4 (EMIN, START, BASE) DLAMC4 subroutine dlamc5 (BETA, P, EMIN, IEEE, EMAX, RMAX) DLAMC5 Function/Subroutine Documentationsubroutine dlamc1 (integerBETA, integerT, logicalRND,…
dlamch.f – SynopsisFunctions/SubroutinesDOUBLE PRECISION function dlamch (CMACH) DLAMCH DOUBLE PRECISION function dlamc3 (A, B) DLAMC3 Function/Subroutine DocumentationDOUBLE PRECISION function dlamc3 (double precisionA, double precisionB)DLAMC3 Purpose: DLAMC3 is intended to force A and B to be stored prior to doing the addition of A and B , for use in situations where optimizers might hold one…
dlamchf77.f – SynopsisFunctions/SubroutinesDOUBLE PRECISION function dlamch (CMACH) DLAMCHF77 deprecated subroutine dlamc1 (BETA, T, RND, IEEE1) DLAMC1 subroutine dlamc2 (BETA, T, RND, EPS, EMIN, RMIN, EMAX, RMAX) DLAMC2 DOUBLE PRECISION function dlamc3 (A, B) DLAMC3 subroutine dlamc4 (EMIN, START, BASE) DLAMC4 subroutine dlamc5 (BETA, P, EMIN, IEEE, EMAX, RMAX) DLAMC5 Function/Subroutine Documentationsubroutine dlamc1 (integerBETA, integerT, logicalRND,…
dlamchf77.f – SynopsisFunctions/SubroutinesDOUBLE PRECISION function dlamch (CMACH) DLAMCHF77 deprecated subroutine dlamc1 (BETA, T, RND, IEEE1) DLAMC1 subroutine dlamc2 (BETA, T, RND, EPS, EMIN, RMIN, EMAX, RMAX) DLAMC2 DOUBLE PRECISION function dlamc3 (A, B) DLAMC3 subroutine dlamc4 (EMIN, START, BASE) DLAMC4 subroutine dlamc5 (BETA, P, EMIN, IEEE, EMAX, RMAX) DLAMC5 Function/Subroutine Documentationsubroutine dlamc1 (integerBETA, integerT, logicalRND,…
dlalsd.f – SynopsisFunctions/Subroutinessubroutine dlalsd (UPLO, SMLSIZ, N, NRHS, D, E, B, LDB, RCOND, RANK, WORK, IWORK, INFO) DLALSD uses the singular value decomposition of A to solve the least squares problem. Function/Subroutine Documentationsubroutine dlalsd (characterUPLO, integerSMLSIZ, integerN, integerNRHS, double precision, dimension( * )D, double precision, dimension( * )E, double precision, dimension( ldb, * )B, integerLDB,…
dlalsa.f – SynopsisFunctions/Subroutinessubroutine dlalsa (ICOMPQ, SMLSIZ, N, NRHS, B, LDB, BX, LDBX, U, LDU, VT, K, DIFL, DIFR, Z, POLES, GIVPTR, GIVCOL, LDGCOL, PERM, GIVNUM, C, S, WORK, IWORK, INFO) DLALSA computes the SVD of the coefficient matrix in compact form. Used by sgelsd. Function/Subroutine Documentationsubroutine dlalsa (integerICOMPQ, integerSMLSIZ, integerN, integerNRHS, double precision, dimension( ldb,…
dlals0.f – SynopsisFunctions/Subroutinessubroutine dlals0 (ICOMPQ, NL, NR, SQRE, NRHS, B, LDB, BX, LDBX, PERM, GIVPTR, GIVCOL, LDGCOL, GIVNUM, LDGNUM, POLES, DIFL, DIFR, Z, K, C, S, WORK, INFO) DLALS0 applies back multiplying factors in solving the least squares problem using divide and conquer SVD approach. Used by sgelsd. Function/Subroutine Documentationsubroutine dlals0 (integerICOMPQ, integerNL, integerNR, integerSQRE,…
dlaln2.f – SynopsisFunctions/Subroutinessubroutine dlaln2 (LTRANS, NA, NW, SMIN, CA, A, LDA, D1, D2, B, LDB, WR, WI, X, LDX, SCALE, XNORM, INFO) DLALN2 solves a 1-by-1 or 2-by-2 linear system of equations of the specified form. Function/Subroutine Documentationsubroutine dlaln2 (logicalLTRANS, integerNA, integerNW, double precisionSMIN, double precisionCA, double precision, dimension( lda, * )A, integerLDA, double precisionD1,…
dlaisnan.f – SynopsisFunctions/SubroutinesLOGICAL function dlaisnan (DIN1, DIN2) DLAISNAN tests input for NaN by comparing two arguments for inequality. Function/Subroutine DocumentationLOGICAL function dlaisnan (double precisionDIN1, double precisionDIN2)DLAISNAN tests input for NaN by comparing two arguments for inequality. Purpose: This routine is not for general use. It exists solely to avoid over-optimization in DISNAN. DLAISNAN checks for…
dlaic1.f – SynopsisFunctions/Subroutinessubroutine dlaic1 (JOB, J, X, SEST, W, GAMMA, SESTPR, S, C) DLAIC1 applies one step of incremental condition estimation. Function/Subroutine Documentationsubroutine dlaic1 (integerJOB, integerJ, double precision, dimension( j )X, double precisionSEST, double precision, dimension( j )W, double precisionGAMMA, double precisionSESTPR, double precisionS, double precisionC)DLAIC1 applies one step of incremental condition estimation. Purpose: DLAIC1…
dlahrd.f – SynopsisFunctions/Subroutinessubroutine dlahrd (N, K, NB, A, LDA, TAU, T, LDT, Y, LDY) DLAHRD reduces the first nb columns of a general rectangular matrix A so that elements below the k-th subdiagonal are zero, and returns auxiliary matrices which are needed to apply the transformation to the unreduced part of A. Function/Subroutine Documentationsubroutine dlahrd…
dlahr2.f – SynopsisFunctions/Subroutinessubroutine dlahr2 (N, K, NB, A, LDA, TAU, T, LDT, Y, LDY) DLAHR2 reduces the specified number of first columns of a general rectangular matrix A so that elements below the specified subdiagonal are zero, and returns auxiliary matrices which are needed to apply the transformation to the unreduced part of A. Function/Subroutine…
dlahqr.f – SynopsisFunctions/Subroutinessubroutine dlahqr (WANTT, WANTZ, N, ILO, IHI, H, LDH, WR, WI, ILOZ, IHIZ, Z, LDZ, INFO) DLAHQR computes the eigenvalues and Schur factorization of an upper Hessenberg matrix, using the double-shift/single-shift QR algorithm. Function/Subroutine Documentationsubroutine dlahqr (logicalWANTT, logicalWANTZ, integerN, integerILO, integerIHI, double precision, dimension( ldh, * )H, integerLDH, double precision, dimension( * )WR,…
dlagv2.f – SynopsisFunctions/Subroutinessubroutine dlagv2 (A, LDA, B, LDB, ALPHAR, ALPHAI, BETA, CSL, SNL, CSR, SNR) DLAGV2 computes the Generalized Schur factorization of a real 2-by-2 matrix pencil (A,B) where B is upper triangular. Function/Subroutine Documentationsubroutine dlagv2 (double precision, dimension( lda, * )A, integerLDA, double precision, dimension( ldb, * )B, integerLDB, double precision, dimension( 2 )ALPHAR,…
dlagts.f – SynopsisFunctions/Subroutinessubroutine dlagts (JOB, N, A, B, C, D, IN, Y, TOL, INFO) DLAGTS solves the system of equations (T-λI)x = y or (T-λI)Tx = y,where T is a general tridiagonal matrix and λ a scalar, using the LU factorization computed by slagtf. Function/Subroutine Documentationsubroutine dlagts (integerJOB, integerN, double precision, dimension( * )A, double…
dlagtm.f – SynopsisFunctions/Subroutinessubroutine dlagtm (TRANS, N, NRHS, ALPHA, DL, D, DU, X, LDX, BETA, B, LDB) DLAGTM performs a matrix-matrix product of the form C = αAB+βC, where A is a tridiagonal matrix, B and C are rectangular matrices, and α and β are scalars, which may be 0, 1, or -1. Function/Subroutine Documentationsubroutine dlagtm…
dlagtf.f – SynopsisFunctions/Subroutinessubroutine dlagtf (N, A, LAMBDA, B, C, TOL, D, IN, INFO) DLAGTF computes an LU factorization of a matrix T-λI, where T is a general tridiagonal matrix, and λ a scalar, using partial pivoting with row interchanges. Function/Subroutine Documentationsubroutine dlagtf (integerN, double precision, dimension( * )A, double precisionLAMBDA, double precision, dimension( * )B,…
dlags2.f – SynopsisFunctions/Subroutinessubroutine dlags2 (UPPER, A1, A2, A3, B1, B2, B3, CSU, SNU, CSV, SNV, CSQ, SNQ) DLAGS2 computes 2-by-2 orthogonal matrices U, V, and Q, and applies them to matrices A and B such that the rows of the transformed A and B are parallel. Function/Subroutine Documentationsubroutine dlags2 (logicalUPPER, double precisionA1, double precisionA2, double…
dlag2s.f – SynopsisFunctions/Subroutinessubroutine dlag2s (M, N, A, LDA, SA, LDSA, INFO) DLAG2S converts a double precision matrix to a single precision matrix. Function/Subroutine Documentationsubroutine dlag2s (integerM, integerN, double precision, dimension( lda, * )A, integerLDA, real, dimension( ldsa, * )SA, integerLDSA, integerINFO)DLAG2S converts a double precision matrix to a single precision matrix. Purpose: DLAG2S converts a…
dlag2.f – SynopsisFunctions/Subroutinessubroutine dlag2 (A, LDA, B, LDB, SAFMIN, SCALE1, SCALE2, WR1, WR2, WI) DLAG2 computes the eigenvalues of a 2-by-2 generalized eigenvalue problem, with scaling as necessary to avoid over-/underflow. Function/Subroutine Documentationsubroutine dlag2 (double precision, dimension( lda, * )A, integerLDA, double precision, dimension( ldb, * )B, integerLDB, double precisionSAFMIN, double precisionSCALE1, double precisionSCALE2, double…