Release Notes: The suffixes .lb, .ub (lower and upper bound), .status (in the solution), .val (primal value), and .dual (dual value) were implemented in MathProg. It also allows comment records (marked by # in the very first position) in CSV files read with the table statements. They can appear only in their beginning. The glp_cpp API routine to solve the critical path problem was added and documented.
Release Notes: A number of basic GLPK API routines were renamed, keeping downward compatibility. glp_version, glp_term_hook, and glp_mem_usage were added. glpk.h was renamed to conform to C++ environments.
Release Notes: An advanced MIP solver was implemented. Three built-in functions were added to MathProg (sin, cos, atan). Some bugs were fixed. New examples on MathProg were included.
Release Notes: The core simplex method and interior-point method routines were reimplemented and now use a new "storage-by-rows" sparse matrix format (unlike previous versions where linked lists were used to represent sparse matrices). A minor bug was fixed in the lpx_read_cpxlp API routine.
Release Notes: The branch-and-bound solver has been completely re-implemented. New statements for the MathProg language have been implemented. New API routines have been added. Support for the free MPS format has been added. DELI and JNI modules have been removed due to licensing problems.
Release Notes: All API routines were re-implemented using new data structures. Obsolete ones will be kept for backward compatibility for a while. New built-in functions were added to the MathProg language, the glpmps.c code was made reentrant, and bugs in the MathProg language translator were fixed.
Release Notes: This release supports the GNU MathProg modeling language (a subset of the AMPL modeling language). The "GLPK: Modeling Language GNU MathProg" document included is a complete description of GNU MathProg. New glpsol solver version supporting models are written in GNU MathProg. The GLPK/L modeling language is no longer supported, as GNU MathProg completely supersedes all GLPK/L features.
Release Notes: The LP presolver is now used by default in the stand-alone program, and glpsol is provided to the lpx_simplex routine. The GLPK/L language now implements declarations of interval sets. There is also now a GLPK JNI Java interface.
Release Notes: This release includes a preliminary implementation of the branch-and-cut framework, which is a set of data structures and routines intended for solving mixed-integer and combinatorial optimization problems. That framework is best described in the "GLPK: A Preliminary Implementation of the Branch-and-Cut Framework" document. There is a standalone program intended for solving, optimally, the symmetric Travelling Salesman Problem (TSP), that is a classical problem of the combinatorial optimization.
Release Notes: This version includes new editions of the GLPK Reference Manual and the "GLPK: Modeling Language GLPK/L" document. There are several new API routines, and a new version of the standalone glpsol solver (based on the new API, from 3.0) was implemented. The old API routines were removed, as the new API provides all functions from the old API.