v2.0.0

Features

• enable SCIP interface to restrict limits automatically with respect to a variability margin defined by parameter scip.limitspace
• read and write files of problems and solutions in arbitrary arithmetics if the solver library does not provide the functionality
• add objective limit option to the SCIP interface
• experimentally support exact-SCIP with VIPR as underlying certified solver
• support SoPlex as underlying solver

Performance improvements

• restrict solver limit settings automatically in order to accelerate the process by default
• adjust number of batches every round automatically in order to maintain expenditure by default

Interface changes

SolverRetcode:

• add code COMPLETIONFAIL to signal a verification preparation error
• add code CERTIFICATIONFAIL to signal a verification check error

SolverInterface:

• templatize arithmetic type to allow instance precision to be independent from solver precision
• add solution information to signature and return of readInstance() and writeInstance() to enable parsing and providing the reference solution
• move out Retcode and rename to SolverRetcode in order to simplify handling return codes
• make settings argument of doSetup() variable to restrict limit settings
• add method getSolvingEffort() to adapt batch number

New parameters

• expenditure = -1 : calculate the number of batches by ceiled division of the solving effort defined in the solver interface (-1: use original, 0: keep batches)
• default value nbatches = 2 in order to try bisection initially

Fixed bugs

• replace parameter type std::int64_t by long long to avert integral inconsistencies
• write setting files for automatically handled limits instead of for detailed verbosity level in order to ensure reproducibility of limit triggered issues
• use stable sum implementation for activity evaluations consistently
• only cancel scip pointer when ending up in an internal stage in order to avoid freeing aborts
• avoid partial setups in release mode if solver interface functions fail
• resolve negated variables to original variables before building the matrix

Build system

• backdate fmt from 8 to 7 to conform c++ standard 14
• add compile option -ffp-contract=off or /fp:precise to enhance reproducibility across different systems
• provide symlink to scip library in bugger build directory for a reliable unique link at runtime
• introduce cmake parameter BUGGER_ARITHMETIC to select reduction arithmetic throughout templated bugger modifiers among float, double, longdouble, quad, and rational