Spectra stands for Sparse Eigenvalue Computation Toolkit as a Redesigned ARPACK.
It is a C++ library for large scale eigenvalue problems, built on top of Eigen,
an open source linear algebra library.
Spectra is implemented as a header-only C++ library, whose only dependency,
Eigen, is also header-only. Hence Spectra can be easily embedded in C++ projects
that require calculating eigenvalues of large matrices.
