Mon Apr 22 12:00:00 2002 Andrew Makhorin <mao@mai2.rcnet.ru>

        * GLPK 3.0.7 has been released.

        * glpduff.h, glpduff.c, glpspx.h, glpspx1.c, glpspx2.c,
        * glpapi7.c
        These modules were replaced by a new implementation of the
        simplex method and therefore they were removed from the package
        (however they still can be found in the subdirectory 'oldsrc').

        * glprsm1.c
        The routine crash_aa was replaced by a new implementation and
        therefore it was removed from the file 'glprsm1.c'.

        * glplpx.h, glplpx.c, glpspx.h, glpspx1.c, glpspx2.c, glpspx3.c,
        * glpspx4.c, glpapi7.c
        New (currently incomplete) implementation of the simplex method
        components was included in the package.

Thu Mar 28 12:00:00 2002 Andrew Makhorin <mao@mai2.rcnet.ru>

        * GLPK 3.0.6 has been released.

        * glpluf.h, glpluf.c, glpinv.h, glpinv.c
        New version of LU-factorization and basis maintenance routines
        (based on Forrest-Tomlin updating technique) was implemented.

        * glpeta.h, glpeta.c, glpfhv.h, glpfhv.c, glpgel.h, glpgel.c,
        * glppfi.h, glppfi.c, glprfi.h, glprfi.c
        These routines implement some other forms of the basis matrix.
        Now they became obsolete being functionally superseded by the
        new version of basis maintenance routines (see above) and were
        removed from the package (however they still can be found in the
        subdirectory 'oldsrc').

        * glpbbm.c, glprsm.h, glprsm1.h, glprsm2.h, glpspx.h, glpspx2.c,
        * glprsm2.c, glpsol.c
        Necessary changes were made in order to use the new version of
        basis maintenance routines.

Tue Jan 29 12:00:00 2002 Andrew Makhorin <mao@mai2.rcnet.ru>

        * GLPK 3.0.5 has been released.
        Structure of the package was re-organized in order to simplify
        its maintenance.

        * doc/guide.texinfo
        New edition of the document "GLPK User's Guide" was included in
        the distribution. Now the document includes descriptions of some
        additional API routines recently added to the package.

        * doc/newapi.txt
        The document "Additional GLPK API Routines" was removed from the
        distribution, because the corresponding material was included in
        the user's guide (see above).

Mon Dec 10 12:00:00 2001 Andrew Makhorin <mao@mai2.rcnet.ru>

        * GLPK 3.0.4 has been released.

        * glpspx.h, glpspx1.c, glpspx2.c, glpapi/glp_simplex2.h
        A new, more efficient version of the two-phase primal simplex
        method was implemented (advanced initial basis, projected
        steepest edge, recursive computations of solution components).

        * glpapi/glp_call_bbm1.c
        Now LP relaxation can be solved either using rsm1_driver(), or
        using glp_simplex2(). The choice is controlled by the parameter
        'meth' (a member of struct bbm1).

        * sample/glpsol.c
        The new implementation of the simplex method is now used by
        default. The old version is available via --old-sim option.

        * glpmat/gm_scaling.c
        Now this routine displays only two lines: an initial "quality"
        and a final "quality".

        * glplp/prepro_lp.c
        Identifiers 'fmin' and 'fmax' renamed to 'f_min' and 'f_max' in
        order to avoid conflict with <math.h>. The bug was fixed due to
        report provided by Sami Farin <sfarin@ratol.fi>.

Wed Oct 03 12:00:00 2001 Andrew Makhorin <mao@mai2.rcnet.ru>

        * GLPK 3.0.3 has been released.

        * glprsm/harris_row.c, glprsm/harris_col.c
        The relative tolerance used on the first pass of the two-pass
        ratio test was replaced by the absolute tolerance.

        * glprsm/rsm_primal.c, glprsm/rsm_feas.c, glprsm/rsm_dual.c
        The absolute tolerance passed to the two-pass ratio test routine
        was decaresed (for both primal and dual simplex).

        These changes were made in order to improve numerical stability
        of the simplex method.

        * glprsm/glp_call_rsm1.c, glprsm/glp_call_bbm1.c,
        * glprsm/glp_simplex1, glprsm/glp_pivoting.c
        Default form of the inverse was changed from RFI to AFI.

Mon Sep 24 12:00:00 2001 Andrew Makhorin <mao@mai2.rcnet.ru>

        * GLPK 3.0.2 has been released.

        * glpfhv.h, glpfhv.c
        New version of the basis maintaining routines was implemented.
        These routines, which are based on so called FHV-factorization
        (a variety of LU-factorization) and Gustavson's data structures,
        perform the main operations on the basis matrix faster at the
        expense of some worsening numerical accuracy.

        * glprsm.h, glprsm/afi.c
        The routines, which implement AFI (Advanced Form of the
        Inverse) based on FHV-factorization, were added to the package.
        This new form is available via the parameter form = 3 (on API
        level) or via the option --afi (in GLPSOL solver).

        * EFI was renamed to PFI
        In order to correct terminology the acronym EFI (Elimination
        Form of the Inverse) was replaced by PFI (Product Form of the
        Inverse) everywhere in the source code and the documentation.

        * glpset/umalloc.c, glpset/ucalloc.c
        * glpset/get_atom.c, glpset/get_atomv.c
        These memory management routines were changed in order *not* to
        clear allocated memory blocks by binary zeros.

Wed Aug 01 12:00:00 2001 Andrew Makhorin <mao@mai2.rcnet.ru>

        * GLPK 3.0.1 has been released.

        * glpapi/old_api.c, glplp/extract_lp.c, store_lpsol.c
        Old API routines were deleted from the package.

        * include/glpk.h, include/glpapi.h, include/glplp.h
        Specifications of old API routines and data structures were
        removed from the headers.

        * sample/glpsol.c
        New version of the stand-alone solver GLPSOL that now uses new
        API routines was implemented.

        * glpapi/glp_set_row_fctr.c, glpapi/glp_set_col_fctr.c,
        * glpapi/glp_get_row_fctr.c, glpapi/glp_get_col_fctr.c,
        * glpapi/glp_scale_prob.c
        Scaling routines were added.

        * glpapi/glp_write_mps.c
        The routine for writing problem data in MPS format was added.

        * glpapi/glp_simplex1.c
        Comprehensive driver to the simplex method was added.

        * glpapi/glp_pivoting.c
        The routines glp_pivot_in() and glp_pivot_out() intended for
        basis maintaining were added.

        * glprsm/create_rsm.c, glprsm/delete_rsm.c, glprsm/scale_rsm.c,
        * glprsm/build_basis.c
        Additional low level routines related to the simplex method
        were added.

        * glpk.h, glpapi.h, glprsm.h
        Additional specifications for new routines and data structures
        were added.

        * sample/lpglpk30.c
        A non-trivial example was added. It allows using GLPK as a base
        LP solver for Concorde, a program for solving Traveling Salesman
        Problem (TSP). For details see comments in 'lpglpk30.c'.

        * doc/newapi.txt
        The document "Additional GLPK API Routines" that describes some
        new API routines was included.

Thu Jul 19 12:00:00 2001 Andrew Makhorin <mao@mai2.rcnet.ru>

        * GLPK 3.0 has been released.

        Now GLPK is provided with new API, which is intended for using
        the package in more complex algorithmic schemes.

        * glpapi/old_api.c
        All routines related to old API were gathered in one file named
        'old_api.c'.

        * glpapi/*.c
        These routines that implement new API were added to the package.

        * include/glpk.h, include/glpapi.h
        Specifications of new API routines and data structures were
        added to these headers. Specifications of old API routines and
        data structures were locked by #ifdef GLP_OLD_API directive.

        * doc/guide.texinfo
        New edition of the document "GLPK User's Guide" that correspond
        to new API was included.

Thu Jun 14 12:00:00 2001 Andrew Makhorin <mao@mai2.rcnet.ru>

        * GLPK 2.4.1 has been released.

        * doc/glpk_ml.texinfo
        The new document "Modeling Language GLPK/L" was included.

        * doc/glpk_ug.texinfo
        New edition of the document "GLPK User's Guide" was included.

        * doc/language.txt
        The preliminary document "GLPK/L Modeling Language: A Brief
        description" was removed from the distribution, because it has
        been replaced by the new document "Modeling Language GLPK/L".

        * glplang/l_spar.c
        The routine comparison() was re-programmed in order to
        implement the relation operation as specified in the language
        description.

        * glpmip.h, glpmip/*.c
        The partition 'glpmip' was renamed to 'glpbbm'.

Thu May 10 12:00:00 2001 Andrew Makhorin <mao@mai2.rcnet.ru>

        * GLPK 2.4 has been released.

        Now GLPK includes an implementation of a preliminary version of
        the GLPK/L modeling language.

        * glplang.h, glplang/*.c
        The header 'glplang.h' and a set of routines that implements
        the GLPK/L language processor (the partition 'glplang') were
        added to the package.

        * doc/language.txt
        The document "GLPK/L Modeling Language: A Brief Description
        (Supplement to GLPK User's Guide)" in plain text format was
        included in the package (see the file 'language.txt' in the
        subdirectory 'doc' of the distribution).

        * ex/model1.lpm, ex/model2.lpm
        Two examples of model descriptions written in GLPK/L were added
        to the package.

        * sample/glpsol.c
        This program was modified in order: a) to allow processing
        model description written in GLPK/L; b) to allow solving pure
        LP problem using the interior point method.

        * sample/glpipm.c
        This program was removed from the package, because its function
        was passed to the GLPSOL solver.

        * Makefile.in
        This file was changed in order to install the GLPSOL solver
        executable.

Mon Apr 09 12:00:00 2001 Andrew Makhorin <mao@mai2.rcnet.ru>

        * GLPK 2.3 has been released.

        * glpmip.h, glpmip/*.c
        These routines (that implement the branch-and-bound method) were
        re-programmed in order to improve robustness of implementation.
        In particular, heuristic routines were carried out from the main
        driver routine.

        Additional GLPK API routines were documented.

        New edition of the document "GLPK User's Guide" was included in
        the package.

        The preliminary document "Mixed Integer Programming Using GLPK
        Version 2.2 (Supplement to GLPK User's Guide)" was removed from
        the package, because this material was included in GLPK User's
        Guide.

Thu Mar 15 12:00:00 2001 Andrew Makhorin <mao@mai2.rcnet.ru>

        * GLPK 2.2 has been released.

        Now GLPK includes a tentative implementation of the
        branch-and-bound procedure based on the dual simplex method for
        mixed integer linear programming (MIP).

        The preliminary document "Mixed Integer Programming Using GLPK
        Version 2.2 (Supplement to GLPK User's Guide)" was included into
        the package in plain text format (see the file 'mip.txt' in the
        subdirectory 'doc' of the distribution).

        * glpmip.h, glpmip/*.c, glpapi/glp_integer.c
        These routines (that implement the branch-and-bound method) were
        added to the package.

        * sample/glpsol.c
        This program was modified in order to allow solving LP and MIP
        problems.

        * glprsm/rsm_primal.c, glprsm/rsm_dual.c, glprsm/rsm_feas.c,
        * glprsm/rsm1_driver.c
        These routines (which are drivers to basic components of the
        revised simplex method) were added to the package.

Mon Feb 19 12:00:00 2001 Andrew Makhorin <mao@mai2.rcnet.ru>

        * GLPK 2.1 has been released.

        * glprsm.h, glprsm/*.c
        These routines (that implement components of the revised simplex
        method) were re-programmed and documented.

        The document "GLPK Implementation of the Revised Simplex Method"
        was included into the package.

Thu Jan 25 12:00:00 2001 Andrew Makhorin <mao@mai2.rcnet.ru>

        * GLPK 2.0 has been released.

        Now GLPK includes a tentative implementation of the primal-dual
        interior point method for large-scale linear programming (for
        more details see the file `NEWS' in the distribution). A number
        of routines related to the interior point method were added to
        the package.

        * insist.c
        The routine `insist' and the macro of the same name were
        introduced into the package in order to replace the standard
        macro `assert'. Some routines require the expression specified
        in the `assert' macro to be evaluated, but compiling the package
        with NDEBUG option prevents from that. This bug was fixed due to
        bug report provided by Peter A. Huegler <phuegler@bsco.com>.

        * Makefile.in
        Minor bug was fixed due to a patch provided by Alexandre Oliva
        <oliva@lsd.ic.unicamp.br>.

Wed Jan 10 12:00:00 2001 Andrew Makhorin <mao@mai2.rcnet.ru>

        * GLPK 1.1.2 has been released.

        * umalloc.c, ufree.c, create_pool.c, get_atom.c, get_atomv.c
        These routines were changed in order to fix a bug due to
        report provided by Andrew Hood <ajhood@fl.net.au>. Because of
        this bug data alignment error occured on the Sparc computer.

Tue Dec 14 12:00:00 2000 Andrew Makhorin <mao@mai2.rcnet.ru>

        * GLPK 1.1.1 has been released.

        Minor bug was fixed in `Makefile.in'.

        GLPK Library Reference was included.

Mon Nov 27 12:00:00 2000 Andrew Makhorin <mao@mai2.rcnet.ru>

        * GLPK 1.1 has been released.

        Minor changes were made in order to co-ordinate GLPK routines
        with their descriptions.

        GLPK User's Guide was included.

Fri Oct 20 12:00:00 2000 Andrew Makhorin <mao@mai2.rcnet.ru>

        * GLPK 1.0 has been released.
