Version 9 (modified by pbelotti, 12 years ago) (diff)


Couenne, an exact solver for nonconvex MINLPs

Couenne (Convex Over and Under ENvelopes for Nonlinear Estimation) is a branch&bound algorithm to solve Mixed-Integer Nonlinear Programming (MINLP) problems:

The purpose of Couenne is to find global optima of nonconvex MINLPs. Couenne implements linearization, bound reduction, and sophisticated branching methods within a Branch&Bound framework. Its main components are:

  • an expression library;
  • separation of linearization cuts;
  • branching rules;
  • bound tightening methods.

It is distributed on Coin-OR ( under the CPL (Common Public License). The CPL is a license approved by the OSI (Open Source Initiative), thus Couenne is OSI Certified Open Source Software.

Download, installation and usage

Couenne is found on the COIN-OR project page. It can be downloaded with Subversion.

svn co Couenne

To install Couenne, we refer to general installation instructions for COIN-OR projects.

The impatient may want to issue the following commands:

cd Couenne
mkdir build
cd build
../configure -C
make install

The above commands place Couenne in the Couenne/build/bin/ directory, libraries in Couenne/build/lib/, and include files in Couenne/build/include/. An alternative directory can be specified with the --prefix option of configure. For instance, when replacing "../configure -C" above with

../configure -C --prefix=/usr/local

the Couenne executable will be installed in {{/usr/local/bin/}}}, the libraries in /usr/local/lib/, and the include files in /usr/local/include/.

Couenne is run as follows:


where is an AMPL stub (.nl) file. Such files can be generated from AMPL with the command "write gfilename;" (notice the "g" before the file name), for instance.

You may also specify a set of options to tweak the performance of Couenne.

Couenne is maintained by Pietro Belotti (belotti at lehigh dot edu).

Web page:

Dependencies: CoinUtils?, Cbc, Cgl, Clp, Ipopt, Osi (from Coin-OR), ASL (Ampl Solver Library, see

External resources: Coin-OR, Common Public License.

Improve this page, report a bug, contribute to Couenne

As an open-source code, contributions to Couenne are welcome. To submit a contribution to Couenne, please follow the COIN-OR guidelines.

The preferred way to report a bug is to use the ticket system. To report a bug using this system:

  1. Register and login,
  2. Report a bug.

As all Wiki pages, this page is editable, this means that you can modify the contents of this page simply by using your web-browser. First register and login then simply click on the "Edit this page" link at the bottom of the page. WikiFormatting will give you a detailed description of available Wiki formatting commands.



This project was initiated in 2006 within a collaboration between IBM and Carnegie Mellon University, aimed at developing algorithms for MINLP.

Credit should be given to our colleagues in this collaboration: Andreas, Pierre, and Stefan, who developed part of Couenne, and Larry T. Biegler, Gérard Cornuéjols, Ignacio E. Grossmann, Jon Lee, and François Margot.

Each has contributed an essential part of the development of Couenne.