2.2. Change Log¶

2.2.1. V2.0.0¶

Released: 2024/10/24

Introduced MATLAB API along with documentation and examples.

Supported QCP, MIQP and MIQCP modeling.

Add community edition license type.

Added new parameters MIP/EnableLazyConstr, NumericFocus.

2.2.2. V1.3.0¶

Released: 2024/07/24

Added new parameters MIP/NumericFocus to set efforts spent on detecting and handling numerical that may occur.

Added some examples about java/c# sdk.

Algorithm performance improvements and bug fixes.

2.2.3. V1.2.1¶

Released: 2024/05/10

Added new parameters OutputFlag, LogToConsole, LogFile are used to control output logs.

Fixed the defect of too many iterations when solving some QP problems.

2.2.4. V1.2.0¶

Released: 2024/04/10

Added new parameter PostScaling.

2.2.5. V1.1.0¶

Released: 2024/01/30

MILP and QP algorithm performance improvements.

Added 5 new tunable parameters for MILP.

Added new parameter SolutionNumber to retrieve multiple suboptimal solutions of MIP solving process.

Introduced C# API along with documentation and examples.

Support for invoking MindOpt in Julia using JuMP and AmplNLWriter.jl packages.

Refined the license verification scheme.

Bug fixes

Fix a precision bug in writing Lpf.

Fix a bug in reporting solution time for concurrent optimization.

Fix an iteration limit bug for concurrent optimization.

Fix a bug in hot-start for simplex method.

Fix a bug in counting dense columns for QP problems.

Fix a bug in preprocessing for QP problem.

2.2.6. V1.0.1¶

Released: 2023/11/20

Add a new license type to support the purchase of solver licenses for a custom time.

Algorithm performance improvements and bug fixes.

2.2.7. V1.0.0¶

Released: 2023/10/12

Introduce a new MindOpt SDK API and corresponding code examples

Add features like MILP’s warm start, SOS constraints and Indicator constraints

Add IIS solving functionality, and upgrade LP’s IIS solving module

Add Callback functionality

Add support for qps format for input files

Improve pipeline of concurrent optimization methods

Providing primal-dual feasible solution for LP

Algorithm performance improvements and bug fixes

2.2.8. V0.25.0¶

Release date: 2023/08/08

Improved the performance and the numerical stability of the interior point solver.

Improved the performance of Python API.

Improved the stability of the IIS algorithm.

Intorudced new IIS algorithm for MILP.

API changes

New error codes:

MDO_INVALID_ARGUMENT (-3), MDO_IIS_NUMERIC (-30000), MDO_IIS_NO_SOLN (-3004), MDO_IIS_FEASIBLE (-3005).

New attributes:

C API: MDO_INT_ATTR_ROW_IIS, MDO_INT_ATTR_COL_IIS.

C++ API: MDO_INT_ATTR::ROW_IIS, MDO_INT_ATTR::COL_IIS.

Python API: MDO_INT_PARAM.ROW_IIS, MDO_INT_ATTR.COL_IIS.

JAVA API: INT_ATTR::ROW_IIS, INT_ATTR::COL_IIS.

Updated APIs:

C API: Mdo_computeIIS.

C++ API: MdoModel::computeIIS.

Python API: MdoModel.compute_iis.

JAVA API: MdoModel::computeIIS.

New integer parameters:

C API: MDO_INT_PARAM_MIP_MAX_STALLING_NODES, MDO_INT_PARAM_MIP_MAX_SOLS, MDO_INT_PARAM_MIP_DETECT_DISCONNECTED_COMPONENTS, MDO_INT_PARAM_MIP_SOLUTION_POOL_SIZE, MDO_INT_PARAM_MIP_ALLOW_DUAL_PRESOLVE.

C++ API: MDO_INT_PARAM::MIP_MAX_STALLING_NODES, MDO_INT_PARAM_MIP_MAX_SOLS, MDO_INT_PARAM::MIP_DETECT_DISCONNECTED_COMPONENTS, MDO_INT_PARAM::MIP_SOLUTION_POOL_SIZE, MDO_INT_PARAM::MIP_ALLOW_DUAL_PRESOLVE.

Python API: MDO_INT_PARAM.MIP_MAX_STALLING_NODES, MDO_INT_PARAM.MIP_MAX_SOLS, MDO_INT_PARAM.MIP_DETECT_DISCONNECTED_COMPONENTS, MDO_INT_PARAM.MIP_SOLUTION_POOL_SIZE, MDO_INT_PARAM.MIP_ALLOW_DUAL_PRESOLVE.

JAVA API: INT_PARAM::MIP_MAX_STALLING_NODES, INT_PARAM_MIP_MAX_SOLS, INT_PARAM::MIP_DETECT_DISCONNECTED_COMPONENTS, INT_PARAM::MIP_SOLUTION_POOL_SIZE, INT_PARAM::MIP_ALLOW_DUAL_PRESOLVE.

New real parameters:

C API: MDO_REAL_PARAM_MIP_LINEARIZATION_BIG_M, MDO_REAL_PARAM_MIP_CUTOFF.

C++ API: MDO_REAL_PARAM::MIP_LINEARIZATION_BIG_M, MDO_REAL_PARAM::MIP_CUTOFF.

Python API: MDO_REAL_PARAM.MIP_LINEARIZATION_BIG_M, MDO_REAL_PARAM.MIP_CUTOFF.

JAVA API: REAL_PARAM::MIP_LINEARIZATION_BIG_M, REAL_PARAM::MIP_CUTOFF.

Bug fixes

Fixed an API bug related to SDP.

Fixed a performance issue related to row deletion.

Fixed a few bugs in MPS reader and LPF reader.

2.2.9. V0.24.1¶

Released: 2023/04/23

Add Linux ARM and Apple Silicon installation packages, Installer Download

Add pip install for Python library, see Method 1: Install via pip install (recommended)

Improve MILP solver performance

Rename data desensitization interface names as --sanitize and --undo_sanitize, see Data Desensitization

2.2.10. V0.24.0¶

Released: 2023/03/30

Improve performance of the MILP solver. Official release version. All cloud authentication accounts are open to use, and there is no need to apply for a special license

Improve performance of concurrency optimization methods

Redesign code in IPM’s Cholesky factorization

API changes

Add a new command line function for data desensitization, see Data Desensitization for details:

--desensitize is used to desensitize the model file of the optimization problem. By removing the data with business information such as variable names and constraint names, only the numerical data that cannot see the business scenario is left

--sensitize is used to restore sensitized files

New integer parameters:

C API: MDO_INT_PARAM_MIP_AUTO_CONFIGURATION

C++ API: MDO_INT_PARAM::MIP_AUTO_CONFIGURATION

Python API: MDO_INT_PARAM.MIP_AUTO_CONFIGURATION

JAVA API: MDO_INT_PARAM::MIP_AUTO_CONFIGURATION

Added error code:

MDO_MODEL_INVALID_CHAR_ATTR (-2014), MDO_MODEL_INVALID_ATTR_NAME (-2019)

Bug fixes

Fix the bug of Mdo_loadProb API

Fix the bug of LP writer and MPS writer, and fix the bug of writing GZ/BZ2 compression format

Fix a bug related to Mdo_copyMdl

Fix a minor bug in the AMPL application (mindoptampl)

2.2.11. V0.23.1¶

Released: 2022/12/21

Add an installation package for the Apple M1 chip

2.2.12. V0.23.0¶

Released: 2022/11/25

Add Semi-Definite Programming (SDP) related APIs, add support for dat-s format for input files

Add the .nl format documentation description. There are .nl file examples in the ampl folder of the installation package examples, which can be directly invoked with the mindoptampl filename.nl command

Fix a small bug in LPF reader

Fix some bugs in MILP solution

API changes

Update APIs:

C API: Mdo_loadModel, Mdo_addRows, Mdo_addCols, Mdo_setColNames, Mdo_setRowNames, Mdo_readProb

C++ API: MdoModel::readProb

Python API: MdoModel.read_prob

JAVA API: MdoModel::readProb

Add APIs:

C API: Mdo_addSymMat, Mdo_addSymMats, Mdo_replaceSymMatObjs, Mdo_replaceSymMatElements, Mdo_getRealAttrSymMat, Mdo_copyMdl

C++ API: MdoModel::addSymMat, MdoModel::addSymMats, MdoModel::replaceSymMatObjs, MdoModel::replaceSymMatElements, MdoModel::getRealAttrSymMat, MdoModel::MdoModel

Python API: MdoModel.add_sym_mat, MdoModel::add_sym_mats, MdoModel::replace_sym_mat_objs, MdoModel::replace_sym_mat_elements, MdoModel::get_real_attr_sym_mat, MdoModel::copy_model

JAVA API: MdoModel::addSymMat, MdoModel::addSymMats, MdoModel::replaceSymMatObjs, MdoModel::replaceSymMatElements, MdoModel::getRealAttrSymMat, MdoModel::copyModel

Add error codes:

MDO_MODEL_INVALID_SYM_MAT_IDX (-2006), MDO_MODEL_INVALID_SYM_MAT_ROW_IDX (-2007), MDO_MODEL_INVALID_SYM_MAT_COL_IDX (-2008), MDO_MODEL_INVALID_REAL_ATTR_SYM_MAT (-2013)

Change error codes:

MDO_LIB_FOLDER_NOT_FOUND (-12) is replaced by MDO_DLL_ERROR (-12)

Add properties:

C API: MDO_REAL_ATTR_SYM_MAT_PRIMAL_SOLN, MDO_REAL_ATTR_MIP_GAP_ABS, MDO_REAL_ATTR_MIP_GAP_REL

C++ API: MDO_REAL_ATTR::SYM_MAT_PRIMAL_SOLN, MDO_REAL_ATTR::MIP_GAP_ABS, MDO_REAL_ATTR::MIP_GAP_REL

Python API: MDO_REAL_ATTR.SYM_MAT_PRIMAL_SOLN, MDO_REAL_ATTR.MIP_GAP_ABS, MDO_REAL_ATTR.MIP_GAP_REL

JAVA API: REAL_ATTR_SYM_MAT_PRIMAL_SOLN, REAL_ATTR_MIP_GAP_ABS, REAL_ATTR_MIP_GAP_REL

2.2.13. Previous version¶

2.2.13.1. V0.20.2 (Released: 2022/10/24)¶

Fix some bugs

2.2.13.2. V0.20.1 (Released: 2022/09/21)¶

Optimize algorithms for solving mixed integer linear programming problems (MILP)
Fix some bugs

2.2.13.3. V0.20.0 (Released: 2022/08/31)¶

Add a branch-and-cut solver for solving Mixed-Integer Linear Programming (MILP) problems.
Add support for Mixed Integer Linear Programming (MILP) interfaces to AMPL.
Optimize license verification. New authentication logic modification:
- For optimization problems with less than 300 variables and constraints, it can be solved without a license authorization file (mindopt.lic or fl_client.ini).
- A license is only required to solve LP and QP problems with more than 300 variables and constraints. The license self-service application method that has been launched can obtain the authorization file. Please refer to License Setup.
- Note: For the license of MILP-type problem solving, it is only supported to send us an email application, and then manually grant permissions. Please refer to the contact information provided in Contact Us.
Optimize installation package:
- The installation script on Linux and macOS is optimized. No additional parameters are required when running the script. The installation path will be confirmed interactively when the script is running. It also supports custom paths. Environment variables are automatically configured after the installation is complete. Repeated Windows installations will remind you.
Fix the following bugs:
- Optimize MdoEnv related
- Fix a bug where the objective maximized mutual QPS readers
- Fix a bug related to objective scaling
- Fix a minor bug related to the Interior point method
- Fix a bug in dual solution output
Add the following APIs:
- C API: Mdo_relaxIntegrality
- C++ API: MdoModel::relaxIntegrality
- Python API: MdoModel.relax_integrality
- JAVA API: MdoModel.relaxIntegrality
Add new exception return codes:
- MDO_ABORT_NODE_LIMIT (-9003), MDO_ABORT_STALLING_NODE_LIMIT (-9004), MDO_ABORT_SOLVER_NOT_AVAILABLE (-9012)
- And modify the code value of a return code MDO_ABORT_INVALID_METHOD from -9003 to -9011
New integer parameters:
- String: MIP/MaxNodes, MIP/RootParallelism
- C API: MDO_INT_PARAM_MIP_MAX_NODES, MDO_INT_PARAM_MIP_ROOT_PARALLELISM
- C++ API: MDO_INT_PARAM::MIP_MAX_NODES, MDO_INT_PARAM::MIP_ROOT_PARALLELISM
- Python API: MDO_INT_PARAM.MIP_MAX_NODES, MDO_INT_PARAM.MIP_ROOT_PARALLELISM
- JAVA API: MDO.INT_PARAM_MIP_MAX_NODES, MDO.INT_PARAM_MIP_ROOT_PARALLELISM
New real parameter:
- String: MIP/IntegerTolerance, MIP/ObjectiveTolerance, MIP/GapAbs, MIP/GapRel
- C API: MDO_REAL_PARAM_MIP_INTEGER_TOLERANCE, MDO_REAL_PARAM_MIP_OBJECTIVE_TOLERANCE, MDO_REAL_PARAM_MIP_GAP_ABS, MDO_REAL_PARAM_MIP_GAP_REL
- C++ API: MDO_REAL_PARAM::MIP_INTEGER_TOLERANCE, MDO_REAL_PARAM::MIP_OBJECTIVE_TOLERANCE, MDO_REAL_PARAM::MIP_GAP_ABS, MDO_REAL_PARAM::MIP_GAP_REL
- Python API: MDO_REAL_PARAM.MIP_INTEGER_TOLERANCE, MDO_REAL_PARAM.MIP_OBJECTIVE_TOLERANCE, MDO_REAL_PARAM.MIP_GAP_ABS, MDO_REAL_PARAM.MIP_GAP_REL
- JAVA API: MDO.REAL_PARAM_MIP_INTEGER_TOLERANCE, MDO.REAL_PARAM_MIP_OBJECTIVE_TOLERANCE, MDO.REAL_PARAM_MIP_GAP_ABS, MDO.REAL_PARAM_MIP_GAP_REL
New parameters in the AMPL interface:
- Integer parameters: mip_max_nodes, mip_root_parallelism
- Real parameters: mip_gap_abs, mip_gap_rel, mip_integer_tolerance, mip_objective_tolerance
Command changes for command-line tools:
- Update directive: - -disable_file_output (or -d): Disable output of the solver’s solution (.bas and .sol files)
- New directives have been added: - -relax (or -r): Relax all integerity requirements in the problem

2.2.13.4. V0.19.0 (Released 2022/04/10)¶

Improve stability of simplex method and interior point method
The license manager is redesigned
The AMPL interface is updated to support convex QP problems
Fix the following bugs:
- Fix a minor bug related to the simplex method
- Fix a bug related to the concurrent optimization method
Add the following APIs:
- C API: Mdo_createEnv, Mdo_freeEnv, Mdo_createMdlWithEnv, Mdo_deleteAllElements, Mdo_deleteAllQuadraticElements
- C++ API: MdoModel::deleteAllElements, MdoModel::deleteAllQuadraticElements
- Python API: MdoModel.delete_all_elements, MdoModel.delete_all_quadratic_elements
- JAVA API: MdoModel.deleteAllElements, MdoModel.deleteAllQuadraticElements
- Add C++/Python/JAVA class MdoEnv to save MindOpt global environment. This is not necessary, but if this global environment is created then it must be passed to MdoModel as part of the constructor parameters

2.2.13.5. V0.16.0 (Released 2022/01/30)¶

Improve stability of simplex method and interior point method
Add convex Quadratic Programming (QP) (Convex QP) interior point method
Fix some bugs in API (Mdo_setElements).
Add the following APIs:
- C API: Mdo_setQuadraticElements, Mdo_getQuadraticElements, Mdo_deleteQuadraticElements
- C++ API: MdoModel::setQuadraticElements, MdoModel::getQuadraticElements, MdoModel::deleteQuadraticElements
- Python API: MdoModel.set_quadratic_elements, MdoModel.get_quadratic_elements, MdoModel.delete_quadratic_elements
- JAVA API: MdoModel.setQuadraticElements, MdoModel.getQuadraticElements, MdoModel.deleteQuadraticElements
Add parameter names and attribute names, such as:
- C API: MDO_INT_PARAM_METHOD, MDO_INT_ATTR_MIN_SENSE, etc.
- C++ API: MDO_INT_PARAM::METHOD, MDO_INT_ATTR::MIN_SENSE, etc.
- Python API: MDO_STR_PARAM.METHOD, MDO_INT_ATTR.MIN_SENSE, etc.
- JAVA API: MDO.INT_PARAM_METHOD, MDO.INT_ATTR_MIN_SENSE, etc.

2.2.13.6. V0.15.1 (Released 2021/10/30)¶

Fix some bugs in network flow simplex method
Python 3.10 is supported

2.2.13.7. V0.15.0 (Released 2021/09/30)¶

Add network flow simplex method and multithreaded simplex method
Improve stability of simplex method and interior point method
Optimize the data reading module

API changes

Add the following API:
- C API: Mdo_setStrAttr, Mdo_getStrAttr
- C++ API: MdoModel::setStrAttr, MdoModel::getStrAttr
- Python API: MdoModel.set_str_attr, MdoModel.get_str_attr
Add the following integer parameters: EnableNetworkFlow, SPX/PrimalPricing, SPX/DualPricing
Change the following integer parameters: Presolve, Method
Add model properties: ProbName
Add return error code: MDO_HOME_ENV_NOT_FOUND, MDO_LIB_FOLDER_NOT_FOUND

2.2.13.8. V0.14.0 (Released 2021/08/30)¶

Improve stability of simplex method and interior point method
Add IIS API for C/CPP/Python (beta)
Add support for Floating License (Trial)
Add Python quicksum API, and optimize the design of Python API
Add AMPL/Pyomo modeling language interface and application, and corresponding examples
Add support for Java API

BUG FIX

API bug fixes

2.2.13.9. V0.13.0 (Released 2021/03/15)¶

Improve API functions, such as adding rows and columns in batches, etc.
Improve performance and numerical stability for simplex and interior point methods
Support for the modeling language PuLP
Support user-defined environment variables to specify the storage directory of license files

API changes

Add the following integer parameter: "SPX/CrashStart"
Change the following integer properties: "Spx/NumIters" to "SPX/NumIters"

2.2.13.10. V0.12.1 (Released 2021/01/11)¶

Improve Python installation steps
Support Python 3.9
Improve the solution efficiency of interior point method

2.2.13.11. V0.12.0 (Released 2020/12/15)¶

Support for remote computing services

2.2.13.12. V0.11.1 (Released 2020/12/08)¶

Update the output method and fixed some minor issues

2.2.13.13. V0.11.0 (Released 2020/11/30)¶

Add new C++ API and Python API
Add new interior point method and concurrent optimization method
Improve performance and numerical stability of the simplex method

Bug fix

Fix a bug related to the output solution
Fix bugs in LP reader

API changes

Add the following integer parameter: “IPM/MaxIterations”
Add the following real parameters: “SolutionTime”, “IPM/PrimalTolerance”, “IPM/DualTolerance”, and “IPM/GapTolerance”

2.2.13.14. V0.10.0 (Released 2020/09/02)¶

Improve simplex algorithm
Add new API to output solution and basis to file
Output solutions and basis to file when using command line tools

2.2.13.15. V0.9.1 (Released 2020/08/26)¶

Fix a bug related to debug messages
Fix symbol issue
Improve license manager

2.2.13.16. V0.9.0 (Released 2020/08/14)¶

This is the first public release of MindOpt