[SCIP] SCIP Optimization Suite 10.0.0 BETA

[Stefan Vigerske]

Hi,

with every day, we are getting closer to release the next major version 
of the SCIP Optimization Suite, the first one with a double-digit major 
version number! Next to achieving this important goal, there are also 
many new features coming with this release again, in particular for GCG 
and SCIP.

We invite everyone to test out the current **release candidate**, in 
source or prebuild binary form, available at

        https://www.scipopt.org/index.php#download

See https://scipopt.org/index.php#contact for options to give feedback.

The final version will be accompanied by a detailed release report 
again. For this e-mail, I can give a quick list of major features added:

For SCIP:
- a new solving mode that allows to **solve rational MILPs exactly**, 
i.e., without numerical tolerances and without being affected by 
floating-point roundoff errors
- a new presolver for detecting implied integral variables and a more 
flexible specification of implied integrality information
- generalizations of symmetry handling methods to reflection symmetries
- a new cut-based conflict analysis
- a new separator for flower inequalities derived from multilinear problems
- two new primal heuristics that exploit user-given decompositions
- improved branching strategies
- a tool to find explanations for infeasibility via so-called 
irreducible infeasible subsystems
- enhancements to the Benders' decomposition framework
- an interface to the nonlinear programming solver CONOPT
- JSON export of SCIP's statistics

For GCG:
- new data structures and file formats for storing decompositions
- newly developed solvers for pricing problems
- parallelization of pricing
- support for handling branching and cutting decisions formulated
directly in the extended formulation variables

For more details, also including API changes, see the following CHANGELOG's:
- GCG: https://github.com/scipopt/gcg/blob/v40-bugfix/CHANGELOG
- PaPILO: https://github.com/scipopt/papilo/blob/main/CHANGELOG
- SCIP: https://www.scipopt.org/doc-10.0.0/html/RN10.php
- SoPLEX: https://soplex.zib.de/doc-8.0.0/html/CHANGELOG.php
- ZIMPL: https://github.com/scipopt/zimpl/blob/master/CHANGELOG

Note that with this version, GCG and PaPILO are licensed under the 
Apache license.

Enjoy,
Stefan