HP Fortran for OpenVMS
HP Fortran for OpenVMS
• Solve the linear equality constrained least squares
(LSE) problem
• Solve the Gauss-Markov linear model problem
• Perform LQ factorization without pivoting
• Unblocked LQ factorization
• Solve underdetermined linear system (based on LQ
factorization)
• Generate a real orthogonal or complex unitary matrix
as a product of Householder matrices
• Unblocked generation of real orthogonal or unitary
matrix
• Multiply a matrix by a real orthogonal or complex uni-
tary matrix by applying a product of Householder ma-
trices
• Unblocked version of multiplication of a matrix by a
real orthogonal or complex unitary matrix by applying
a product of Householder matrices
• Reduce a square matrix to upper Hessenberg form
• Unblocked version of square matrix reduction
• Reduce a symmetric matrix to real symmetric tridiag-
onal form
• Reduce a band matrix to bidiagonal form
• Unblocked version of symmetric matrix reduction
• Reduce a rectangular matrix to bidiagonal form
• Reduce a band symmetric/Hermitian matrix to tridi-
agonal form
• Reduce a symmetric/Hermitian-definite banded gen-
eralized eigenproblem to standard form
• Compute various norms of a complex Hermitian tridi-
agonal matrix
• Compute eigenvalues and optional Schur factoriza-
tion or eigenvectors using QR algorithm
• Compute selected eigenvectors by inverse iteration
• Compute eigenvectors from Schur factorization
• Compute eigenvectors using the Pal-Walker-Kahan
variant of the QL or QR algorithm
• For a pair of N-by-N real nonsymmetric matrices,
compute the generalized eigenvalues, the real Schur
form, and the left and/or right Schur vectors
• For a pair of N-by-N real nonsymmetric matrices,
compute the generalized eigenvalues, and the left
and/or right generalized eigenvectors
• Solve the generalized nonsymmetric eigenproblem
Ax = lambda Bx
• Solve the generalized definite banded eigenproblem
Ax = lambda Bx
• Solve the generalized symmetric/Hermitian-definite
banded eigenproblem
• Solve the symmetric eigenproblem using divide-and-
conquer algorithm
• Compute singular values and, optionally, singular
vectors using the QR algorithm
• Compute the generalized (quotient) singular value
decomposition
• Compute the generalized singular value decompo-
sition (GSVD) on the M-by-N matrix A and P-by-N
matrix B
• Solve a generalized linear regression model problem
Sparse System Solver Subprograms
The CXML Sparse System Solver library contains a set
of subprograms that can be used to solve sparse linear
systems of equations. Two packages providing direct
and iterative methods are supported.
Direct Method Sparse Solver Package:
The direct solver package includes skyline (profile)
solvers for symmetric and nonsymmetric matrices. Sep-
arate factorization and solver routines are provided to
allow repeated use of the solver for multiple right hand
sides, without repeating the factorization. To make
the subprograms easier to use, both simple and ex-
pert driver routines are provided. Functions provided
include:
• LDU factorization
• Solve
• Norm evaluation
• Condition number estimation
• Iterative refinement
• Simple and expert drivers
These storage schemes are supported for symmetric
and nonsymmetric matrices:
• Profile-in storage
• Structurally symmetric, profile-in storage (for non-
symmetric only)
• Diagonal-out storage
Iterative Method Sparse Solver Package:
For the iterative method, the library provides a modular
set of storage schemes, preconditioners, and solvers.
These solvers and preconditioners are easily accessed
through an integrated driver routine.
8