pointers for some libraries, numerical(if available)

[utab]

Dear all,

I have some Stiffness and Mass matrices written out from Ansys(commercia l
Finite Element code) in Harwell Boeing(HB) format. I can read them
through a template library, GMM++. GMM++ can read them in the compressed
column/row formats. My ultimate aim is to use these matrices in some
eigenvalue computations.

I checked that MTL(Matrix Template Library) also has the capabilities of
reading from HB input files(no examples provided however). I did a lot of
search on the net. I came up with a converter here :

http://bebop.cs.berkeley.edu/smc/faq.html#utility-conversion

it is pretty ok for the moment but one problem is that I should use
MATLAB for the matrix operations and command line tool that I built in
Linux to make necessary conversions.

I am converting the HB matrices to matrix market formatted files and then
reading them into MATLAB with the routines given on the Matrix Market
website.

What I would like to do, if I can, to stay in C++, complete all the read,
and eigen computations in C++ language. Actually, I am looking for some
libraries(or some combinations) which are capable of the doing above
mentioned points.

Is there someone who can shed some light on these points and provide some
pointers which could help me.

Best,
U.