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This method is the general entry point for writing optimization data to a file. It can be used to write optimization models, solutions vectors, basis vectors, start vectors, or parameter settings. The type of data written is determined by the file suffix. File formats are described in the File Format section.

Note that writing a model to a file will process all pending model modifications. This is also true when writing other model information such as solutions, bases, etc.

Note also that when you write a Gurobi parameter file (PRM), both integer or double parameters not at their default value will be saved, but no string parameter will be saved into the file.

void write ( String filename )


filename: The name of the file to be written. The file type is encoded in the file name suffix. Valid suffixes are .mps, .rew, .lp, or .rlp for writing the model itself, .dua or .dlp for writing the dualized model (only pure LP), .ilp for writing just the IIS associated with an infeasible model (see GRBModel.computeIIS for further information), .sol for writing the solution selected by the SolutionNumber parameter, .mst for writing a start vector, .hnt for writing a hint file, .bas for writing an LP basis, .prm for writing modified parameter settings, .attr for writing model attributes, or .json for writing solution information in JSON format. If your system has compression utilities installed (e.g., 7z or zip for Windows, and gzip, bzip2, or unzip for Linux or macOS), then the files can be compressed, so additional suffixes of .gz, .bz2, or .7z are accepted.

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