On 7 Mar 2008, at 22:06, Andrew Sutton wrote:

...

I am very new to boost, and I thought I'd do some simple linear algebra examples to get started. I got some simple vector/matrix multiplications going with .../boost/numeric/ublas/vector.hpp and matrix.hpp. However, I didn't see any function in the documentation do find eigen values or to do factorizations or anything like that. Are those kinds of functions not included, or am I crazy and just missed them in docs?

You might find something in the ublas library...

They are in the LAPACK library, for which there are ublas bindings in the sandbox Matthias

Hello David,

Ok, I got the bindings out of the sandbox and put them in my .../boost_1_34_1\boost\numeric folder. I downloaded TNT from here: http://math.nist.gov/tnt/tnt126.zip, but it is just 21 .h files and I dont see really any functions that I am looking for.

I don't know TNT in detail, but I guess you would have to also download JAMA (which is available from the TNT webpage), if you need a solver for Eigen vectors. 1) Am I right that you can use atlas OR tnt? No, these are complementary. You can use tnt with bindings+atlas, or with JAMA. You can use uBlas with bindings+atlas. ATLAS and LAPACK are not exactly the same thing. ATLAS provides a complete BLAS implementation, but contains only a subset of the routines provided by LAPACK. I don't know ATLAS in detail, but I don't think that it has a solver for Eigen vectors included directly (I used http://www.netlib.org/lapack/lug/node142.html to dispatch the cryptic Fortran 6 letter names in clapack.h from ATLAS, and they don't seem to match with a solver for Eigen vectors). So you need LAPACK (Fortran) or CLAPACK if you need access to a solver for Eigen vectors. The bindings also work with LAPACK and CLAPACK, so this should be no problem. The JAMA library (from TNT) on the other hand probably contains a solver for eigen vectors.

2) Should I be using TNT instead of lapack?

I personally prefer uBlas + bindings + lapack, but as I already pointed out, I don't know TNT in detail.

3) do the TNT .h files have to be in a particular location?

I guess the bindings expect them to be in a subfolder tnt relative to your include path.

Sorry for the confusion, I've just never used anything with "bindings" before, so I don't know how it works!

Maybe you should have a look at http://lists.boost.org/MailArchives/ublas (ublas@lists.boost.org). Regards, Thomas