From: Martin Reuter <reuter@MIT.EDU>  20110110 21:03:56

Thanks Peter, I was interested in a complex Schur of a single matrix (zgees, I also need ztrsen for reordering afterward). Do you think it makes sense to base that on the generalized case (probably possible by passing the identity matrix for B?). I think it might be better to wrap around zgees directly (that's what I did). About the matlab code, of course the original code is % Copyright 19842005 The MathWorks, Inc. (e.g. "type expm" or "type sqrtm"). but it is rather simple code and I rewrote it in c++. Not sure if it still falls under the copyright? How different does a rewrite need to be? Thanks, Martin On Mon, 20110110 at 18:55 +0000, Peter Vanroose wrote: > Martin, > > I've just added to vxl netlib the necessary lapack files (zgges and its depencencies) for complex Schur. > I've also added a (first attempt of) C++ interface in the new > core/vnl/algo/vnl_complex_generalized_schur.cxx > which is essentially a complexified version of > core/vnl/algo/vnl_generalized_schur.cxx > > Please verify whether this is what you need, and possibly modify or add to what I've committed to SVN. Not tested it thoroughly (but put a minimal test in core/vnl/algo/tests/test_complex_algo.cxx; please extend this). > > Concerning your question on incorporating matlab licensed code into vxl: I've no idea about (and no experience with) this. Maybe someone else on the list can comment on this issue? > > Best regards, > >  Peter. > > > On 20110104 Martin Reuter wrote: > > I wrote a complex Schur (I am not interested in the eigenproblem, just > > the decomposition of a complex matrix, so I wrote a wrapper around zgees > > from LAPACK, also the reordering ztrsen). I could not find those in the > > netlib that comes with VXL. Currently these are just stand alone > > routines that use vnl matrices, but it is not in the form of a vnl > > class. > > > > How can I contribute that code? Also I wrote stuff that might be of > > interest (based on matlab code) to compute: > > > >  sqrt of a matrix (using the Schur decomposition, see matlab sqrtm) > >  exp of a matrix (see matlab expm) > >  log of a matrix (also based on Schur and more, see matlab funm) > >  pow of a matrix (using log and exp) > > > > Can this be incorporated into vnl (expecially what I ported from matlab, > > license)? > > > > > > > > > > >  > > 