Some of the features included in ARPACK++ are:

- The use of templates to reduce the work needed to establish and solve eigenvalue problems and to simplify the structure utilized to handle such problems.
- A friendly interface that avoids the complication of the
*reverse communication interface*that characterizes the FORTRAN version of ARPACK. For instance, the u ser can supply the nonzero elements of a matrix and obtain its eigenvalues and eigenvectors stored using the*Standard Template Library**(STL)*ve ctor class. - The ability to easily find interior eigenvalues and to solve generalized problems. ARPACK++ includes several matrix classes that use routines from SuperLU, UMFPACK and LAPACK to solve linear systems. With these classes, spectral transformations such as the shift and invert method can be employed to find internal eigenvalues of regular and generalized problems without requiring the user to explicit ly solve linear systems.
- A structure that minimizes the work needed to generate an interface between ARPACK and other libraries, such as the
*Template N umerical Toolkit**(TNT)*

ARPACK++ is developed and maintained by Francisco Magalhaes Gomes at UNICAMP .

ARPACK++ can be downloaded from here

A User's Guide for ARPACK++ is also available.

For more information on ARPACK++ look here.