The Armadillo C++ library is provided without any warranty
of fitness for any purpose. You can redistribute the library
and/or modify it under the terms of the GNU Lesser General
Public License (LGPL) as published by the Free Software
Foundation, either version 3 of the License or (at your option)
any later version.

Note that the LGPL v3 is formulated as an extension/modification 
of the GPL v3 license, providing additional permissions.
For example, programs that use Armadillo can be distributed under 
a different license, provided some conditions are met.

A copy of the LGPL and GPL licenses is provided in the 
"licenses/LGPL.txt" and "licenses/GPL.txt" files, respectively.

More info: http://www.opensource.org/licenses