A Framework for Modeling and Solving Mixed-Integer Nonlinear Programming Problems on Networks


Lamatto++ is a framework to model mixed-integer nonlinear programming problems especially on (but not limited to) networks. Lamatto++ is completely written in C++ and has interfaces to CPLEX, GUROBI, SCIP and GAMS, where the latter provides access to a large collection of solvers for roughly all kinds of mathematical programming problems. Lamatto++ major features are a unified modeling API and a single interface to all the above mentioned solvers. Lamatto++ comes with extendable data structures to handle graphs and networks and provides automatic unit conversion for physical values. For data I/O and data exchange with third party software, Lamatto++ makes use of the XML parsing library Xerces.

More details on the aim, functionality, and software design of the Lamatto++ software framework can be found in the references listed below.


We gratefully thank all members of the ForNe project for their help in improving Lamatto++.
Special thanks go to Marc Pfetsch for implementing the Lamatto++ SCIP interface and to Christoph Conrads, Armin Fügenschuh, Ralf Gollmer, Christine Hayn, Benjamin Hiller, Jesco Humpola, Imke Joormann, Thomas Lehmann, Ralf Lenz, Debora Mahlke, Andris Möller, Djamal Oucherif, Henrik Pilz, Lars Schewe, Martin Schmidt, Robert Schwarz,Jonas Schweiger, Claudia Stangl, Jacint Szabo, Stefan Vigerske, Bernhard Willert, and Andrea Zelmer for their active participation.

State of development

Lamatto++ was orginally developed by Björn Geißler, Oliver Kolb and Antonio Morsi in 2007 and is from then on used within the projects:

Technical Transient Optimization of Gas Networks
Odysseus – Diskret-kontinuierliche Optimierung komplexer dynamischer Wasserver- und entsorgungssysteme
Since 2009 Lamatto++ was heavily enhanced when it became a substantial part of the project:

ForNe – Forschungskooperation Netzoptimierung
Up to now, Lamatto++ is still under development and not publicly available.


A. Morsi.
Chapter 5 of Solving MINLPs on Loosely-Coupled Networks with Applications in Water and Gas Network Optimization.
Ph.D. thesis, University of Erlangen-Nuremberg, 2013.


For any further information on Lamatto++, please feel free to contact Antonio Morsi (Antonio.Morsi[at] or Björn Geißler (Bjoern.Geissler[at]