8.1.3. IO management

All API I/O functions related to controlling a model are declared in this file, including

  • reading a model from a file and writing the loaded model to a file.

  • redirecting solver log.

Supported model files are

  • MPS: File extension name must be .mps, .mps.gz, or .mps.bz2.

  • LP: File extension name must be .lp, .lp.gz, or lp.bz2.

  • .dat-s file, used in SDP.

  • .nl file. You can use mindoptampl filename.nl to solve it, more details Verify mindoptampl.

You can find the examples of the files in examples folder in MindOpt installation package.

All API functions related to this.

Examples

MdoMdl * model = NULL;
Mdo_createMdl(&model);

/* Set log */
Mdo_setLogToConsole(model, flag_LogToConsole);
Mdo_setLogFile(model, "logfile.log");

/* Read/write problem */
Mdo_readProb(model, "problem.mps");
Mdo_writeProb(model, "copy_problem.lp");

/* Solve */
Mdo_solveProb(model);

/* Write solution and basis */
Mdo_writeSoln(model, MY_FOLDER "basis.bas");
Mdo_writeSoln(model, MY_FOLDER "solution.sol");

/* Write/read optimization task */
const char * model_file = "./my_model.mdo";
const char * param_file = "./my_param.mdo";
const char * soln_file = "./my_soln.mdo";

Mdo_writeTask(model, model_file, MDO_YES, MDO_NO, MDO_NO);
Mdo_writeTask(model, param_file, MDO_NO, MDO_YES, MDO_NO);
Mdo_writeTask(model, soln_file, MDO_NO, MDO_NO, MDO_YES);

Mdo_readTask(model, model_file, MDO_YES, MDO_NO, MDO_NO);
Mdo_readTask(model, param_file, MDO_NO, MDO_YES, MDO_NO);
Mdo_readTask(model, soln_file, MDO_NO, MDO_NO, MDO_YES);

Functions

MdoResult Mdo_readProb(MdoMdlPtr mdl, const char *filename)

This function reads an optimization problem from a file.

Parameters

  • mdl – Pointer to the model.

  • filename – A character array that specifies the filename.

Return

A response code that specifies the status of the function.

See

Mdo_writeProb()

Note

  • Once the function is called, the previously loaded problem will be abandoned.

  • Note that the type of the inputted model is determined by the file suffix. Valid suffixes are .mps(.bz2/.gz) or .lp(.bz2/.gz) or .dat-s.

MdoResult Mdo_writeProb(const MdoMdlPtr mdl, const char *filename)

This function writes an optimization problem to a file.

Parameters

  • mdl – Pointer to the model.

  • filename – A character array that specifies the filename.

Return

A response code that specifies the status of the function.

See

Mdo_readProb()

Note

Note that the type of the output model is determined by the file suffix. Valid suffixes are .mps(.bz2/.gz) or .lp(.bz2/.gz).

MdoResult Mdo_writeSoln(const MdoMdlPtr mdl, const char *filename)

This function writes an optimization solution to a file.

Parameters

  • mdl – Pointer to the model.

  • filename – A character array that specifies the filename.

Return

A response code that specifies the status of the function.

Note

Note that the type of the optimization solution is determined by the file suffix. Valid suffixes are .sol or .bas.

MdoResult Mdo_readTask(MdoMdlPtr mdl, const char *filename, MdoBool read_model, MdoBool read_param, MdoBool read_soln)

This function loads an optimization model task from a file.

Parameters

  • mdl – Pointer to the model.

  • filename – A character array that specifies the model.

  • read_model – A boolean flag that specifies if the model shall be loaded.

  • read_param – A boolean flag that specifies if the parameters shall be loaded.

  • read_soln – A boolean flag that specifies if the solution shall be loaded.

Return

A response code that specifies the status of the function.

See

Mdo_writeTask()

Note

  • Once the function is called, the previously loaded problem will be abandoned.

  • A model task file includes the problem data, parameter settings, and solutions in a binary format.

MdoResult Mdo_writeTask(const MdoMdlPtr mdl, const char *filename, MdoBool write_model, MdoBool write_param, MdoBool write_soln)

This function writes an optimization model task to a file.

Parameters

  • mdl – Pointer to the model.

  • filename – A character array that specifies the filename.

  • write_model – A boolean flag that specifies if the model shall be outputted.

  • write_param – A boolean flag that specifies if the parameters shall be outputted.

  • write_soln – A boolean flag that specifies if the solution shall be outputted.

Return

A response code that specifies the status of the function.

See

Mdo_readTask()

Note

A model task file includes the problem data, parameter settings, and solutions in a binary format.

MdoResult Mdo_setLogToConsole(MdoMdlPtr mdl, MdoBool flag)

This function specified if the log shall be printed out to screen or not.

Parameters

  • mdl – Pointer to the model.

  • flag – A flag that specified if the log shall be printed out to screen or not.

MdoResult Mdo_setLogFile(MdoMdlPtr mdl, const char *filename)

This function redirects output log to a file.

Parameters

  • mdl – Pointer to the model.

  • filename – Path to the log file.

MdoResult Mdo_setLogCallback(MdoMdlPtr mdl, void (*logcb)(const char *msg, void *userdata), void *userdata)

This function redirects output log to a user-defined callback function.

param mdl

Pointer to the model.

param logcb

User defined callback function.

param userdata

User defined data taht will be passed into the callback function.