License¶
Thank you for using CVX!
The files contained in the CVX distribution come from several different sources and are covered under a variety of licenses. The files owned by CVX Research, Inc. are covered under one of two licenses: the CVX Standard License and the CVX Professional License. The CVX Standard License is effectively the GNU General Public License, Version 2 (GPLv2), but with additional terms that govern modifications that connect CVX to additional solvers. The added terms are discussed in “Solver Interfaces” below.
CVX Professional License¶
The standard CVX distribution includes several files in Matlab p-code format, which contain encrypted binary versions of Matlab bytecode. As their name implies, they are recognized by their .p suffix. Currently the following files are distributed this way:
shims/cvx_mosek.p
shims/cvx_gurobi.p
cvx_license.p
You may redistribute these files only as part of the complete, unmodified CVX package as distributed by CVX Research, Inc. itself.
CVX Standard License¶
If you wish, you may distribute a version of CVX with all of the p-code files removed. The resulting package retains full functionality with the exception of its ability to connect to commercial solvers. This modified package is covered by the CVX Standard License. Under this license, you are free to redistribute and/or modify the files under the terms of the GPLv2, plus the additional terms discussed in “Solver Interfaces” below.
You must include the files LICENSE.txt and GPL.txt in unmodified form when redistributing this software. If you did not receive a copy of either of these files with your distribution, please contact us.
Solver Interfaces¶
CVX relies upon other software packages, called solvers, to perform many of its underlying calculations. Currently CVX supports free solvers SeDuMi and SDPT3, and commercial solvers Gurobi and MOSEK. The resulting nexus of free and commercial software presents a licensing challenge. Our vision is guided by three goals:
- to ensure that CVX remains free to use by all users with any compatible free solver.
- to generate revenue by selling interfaces to commercial solvers to commercial customers.
- to provide the academic community with the full commercial capability at no charge.
The terms we lay out here are intended to support these trifold goals.
We invite our users to create new interfaces between CVX and other free solvers. By “free”, we mean that the solver must be made available at no charge for to all users, including commercial users, without restriction. Please contact us if you are interested in creating such an interface; we can offer assistance. If you do create one, please consider submitting it to us for inclusion in the standard CVX distribution. But you are under no obligation to do this. Instead, you can ship the interface code with the solver itself; or you can construct a modified version of CVX with your interface included.
We do not permit the creation and distribution of new interfaces between CVX and non-free solvers—even if those solvers are made available to academic users at no charge. If you are a vendor or developer of a commercial solver, and would like to develop or offer a CVX interface to your users, please contact us at info@cvxr.com. We welcome the opportunity to support a wider variety of commercial solvers with CVX, and are willing to devote engineering resources to make those connections.
If you are a user of a particular commercial solver and would like to see it supported by CVX, please contact your solver vendor—but please contact us at info@cvxr.com as well. If there is sufficient demand, and it proves technically and financially feasible, we will reach out to the solver vendor to work on an implementation.
Bundled solvers¶
The solvers SDPT3 and SeDuMi are distributed with CVX in the sdpt3/ and sedumi/ subdirectories, respectively. Neither of these packages is owned by CVX Research, Inc. Both are included with permission of the authors, and licensed under the terms of the GPLv2. Please consult the plain-text documentation contained in each of these directories for more information about copying, citation, and so forth.
Example library¶
The contents of the example library, which is distributed with CVX in the examples/ subdirectory, is public domain. You are free to use them in any way you wish; but when you do, we request that you give appropriate credit to the authors. A number of people have contributed to the examples in this library, including Lieven Vandenberghe, Joëlle Skaf, Argyris Zymnis, Almir Mutapcic, Michael Grant, and Stephen Boyd.
No Warranty¶
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
