Arpack software is capable of solving large scale symmetric, nonsymmetric, and generalized eigenproblems from significant application areas. the software is designed to compute a few (k) eigenvalues with user specified features such as those of largest real part or largest magnitude. storage requirements are on the order of n*k locations. no auxiliary storage is required. a set of schur basis vectors for the desired k-dimensional eigen-space is computed which is numerically orthogonal to working precision. numerically accurate eigenvectors are available on request.

important features:

* reverse communication interface.
* single and double precision real arithmetic versions for symmetric,
non-symmetric,
* standard or generalized problems.
* single and double precision complex arithmetic versions for standard or
generalized problems.
* routines for banded matrices - standard or generalized problems.
* routines for the singular value decomposition.
* example driver routines that may be used as templates to implement
numerous shift-invert strategies for all problem types, data types and
precision.
this package provides parpack: the mpi implementation of arpack.

this package contains the shared library.