  This paper introduces a new publicly available numerical library for
cosmology, Cosmo++. The library has been designed using object-oriented
programming techniques, and fully implemented in C++. Cosmo++ introduces a
unified interface for using most of the frequently used numerical methods in
cosmology. Most of the features are implemented in Cosmo++ itself, while a part
of the functionality is implemented by linking to other publicly available
libraries. The most important features of the library are Cosmic Microwave
Background anisotropies power spectrum and transfer function calculations,
likelihood calculations, parameter space sampling tools, sky map simulations,
and mask apodization. Cosmo++ also includes a few mathematical tools that are
frequently used in numerical research in cosmology and beyond. A few simple
examples are included in Cosmo++ to help the user understand the key features.
The library has been fully tested, and we describe some of the important tests
in this paper. Cosmo++ is publicly available at http://cosmo.grigoraslanyan.com
