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Free Modelica library for data I/O of CSV, INI, JSON, MATLAB MAT, SSV, TIR, Excel XLS/XLSX and XML files.

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Library description

ExternData is a utility library to access data stored in CSV, INI, JSON, MATLAB MAT, SSV, TIR, Excel XLS/XLSX or XML files. The aim of this library is to provide access from Modelica simulation tools to data sets for convenient model initialization and parameterization. An overview of the library is provided in

Thomas Beutlich and Dietmar Winkler. Efficient Parameterization of Modelica Models. In: Proceedings of the 14th International Modelica Conference. Ed. by Martin Sjölund, Lena Buffoni, Adrian Pop, and Lennart Ochel. Linköping, Sweden, September 2021. DOI: 10.3384/ecp21181141.

Main features

All data I/O access is implemented using external Modelica functions.


ExternData is released under the terms of the Simplified BSD License.


ExternData is based on the following third-party C projects

  • bsxml-json - Borislav Sapundzhiev's fairly simple XML DOM and JSON implementation
  • expat - James Clark's Expat XML parser library
  • hdf5 - The HDF Group's data model, library and file format for storing and managing data
  • inih - Ben Hoyt's simple INI file parser in C
  • libxls - David Hoerl's C library for parsing Excel files
  • libxml2 - Daniel Veillard's XML C parser and toolkit of Gnome
  • matio - Christopher Hulbert's C library for reading and writing MATLAB MAT-files
  • minizip - Gilles Vollant's Zip and UnZip library
  • parson - Krzysztof Gabis' lightweight JSON library written in C
  • uthash - Troy D. Hanson's C macros for hash tables and more
  • zlib - Jean-loup Gailly's and Mark Adler's massively spiffy yet delicately unobtrusive compression library
  • zstring - Fehmi Noyan ISI's string processing library for C


Use the following BibTeX lines to cite the ExternData library.

  title = {{Efficient Parameterization of Modelica Models}},
  author = {Beutlich, Thomas and Winkler, Dietmar},
  pages = {141--146},
  doi = {10.3384/ecp21181141},
  booktitle = {Proceedings of the 14th International Modelica Conference},
  location = {Link\"oping, Sweden},
  editor = {Sj\"olund, Martin and Buffoni, Lena and Pop, Adrian and Ochel, Lennart},
  isbn = {978-91-7929-027-6},
  issn = {1650-3740},
  month = sep,
  series = {Link\"oping Electronic Conference Proceedings},
  number = {181},
  publisher = {Modelica Association and Link\"oping University Electronic Press},
  year = {2021}

Development and contribution

You may report any issues with using the Issues button.

Contributions in shape of Pull Requests are always welcome.