Blitz++ is a C++ template class library that provides high-performance multidimensional array containers for scientific computing.
Blitz++ has gone through some changes in location:
The original Blitz++ website was located at
http://oonumerics.org/blitz(archived at http://www.math.unipd.it/~michela/OP.htm).
Blitz++ then moved to SourceForge, at http://www.sourceforge.net/projects/blitz.
The latest maintained version of Blitz++ is now on GitHub, at https://github.com/blitzpp/blitz
Diverse information on Blitz++ is now being catalogued at the GitHub wiki: http://github.com/blitzpp/blitz/wiki/
Licensing information is detailed in the LEGAL file. Summary: you can do anything except sell this library in source form. Blitz is licensed under either the Lesser GPL version 3 license (see COPYING and COPYING.LESSER), the BSD license (see COPYRIGHT), and the less restrictive Perl "artistic license" version 2.0 (see LICENSE).