Linear Algebra Library
Double Precision Real

LINPACK_D is a FORTRAN77 library which can solve systems of linear equations for a variety of matrix types and storage modes, by Jack Dongarra, Jim Bunch, Cleve Moler, Pete Stewart.

LINPACK has officially been superseded by the LAPACK library. The LAPACK library uses more modern algorithms and code structure. However, the LAPACK library can be extraordinarily complex; what is done in a single LINPACK routine may correspond to 10 or 20 utility routines in LAPACK. This is fine if you treat LAPACK as a black box. But if you wish to learn how the algorithm works, or to adapt it, or to convert the code to another language, this is a real drawback. This is one reason I still keep a copy of LINPACK around.

Versions of LINPACK in various arithmetic precisions are available through the NETLIB web site.


The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.


LINPACK_D is available in a C version and a C++ version and a FORTRAN77 version and a FORTRAN90 version and a MATLAB version and a Python version.

Related Data and Programs:

BLAS1_D, a FORTRAN77 library which contains basic linear algebra routines for vector-vector operations, using double precision real arithmetic.

LAPACK_EXAMPLES, a FORTRAN77 program which demonstrates the use of the LAPACK linear algebra library.

LINPACK_BENCH, a FORTRAN77 program which measures the time taken by LINPACK to solve a particular linear system.

LINPACK_C, a FORTRAN77 library which is a version of LINPACK for single precision complex arithmetic.

LINPACK_S, a FORTRAN77 library which is a version of LINPACK for single precision real arithmetic.

LINPACK_Z, a FORTRAN90 library which is a version of LINPACK for double precision complex arithmetic.

LINPLUS, a FORTRAN77 library which carries out some linear algebra operations on matrices stored in formats not handled by LINPACK.

NMS, a FORTRAN77 library which includes LINPACK.

QR_SOLVE, a FORTRAN77 library which computes the least squares solution of a linear system A*x=b.

SLATEC, a FORTRAN90 library which includes LINPACK.

TEST_MAT, a FORTRAN77 library which defines test matrices, some of which have known determinants, eigenvalues and eigenvectors, inverses and so on.

TOEPLITZ_CHOLESKY, a FORTRAN77 library which computes the Cholesky factorization of a nonnegative definite symmetric Toeplitz matrix.


Jack Dongarra, Jim Bunch, Cleve Moler, Pete Stewart.


  1. Jack Dongarra, Jim Bunch, Cleve Moler, Pete Stewart,
    LINPACK User's Guide,
    SIAM, 1979,
    ISBN13: 978-0-898711-72-1,
    LC: QA214.L56.
  2. Charles Lawson, Richard Hanson, David Kincaid and Fred Krogh,
    Algorithm 539, Basic Linear Algebra Subprograms for Fortran Usage,
    ACM Transactions on Mathematical Software,
    Volume 5, Number 3, September 1979, pages 308-323.

Source Code:

Examples and Tests:

List of Routines:

You can go up one level to the FORTRAN77 source codes.

Last revised on 10 May 2006.