Hello,

  I've attached a patch which implements eigenvector support for
real nonsymmetric matrices. The algorithm used is backsubstitution
to find eigenvectors of the Schur form, followed by backtransformation
by the Schur vectors. I followed the lapack code closely (dtrevc),
so this implementation handles degeneracies very well.

  The patch includes:

  * unsymmv.c - all the eigenvector stuff
  * updated eigen.texi to give documentation on all new functions plus
    an example
  * updated eigen/sort.c to add gsl_eigen_unsymmv_sort()

  I also attached a new test program which no longer needs lapack
to verify the results. I haven't added anything to eigen/test.c yet.

Patrick Alken