**LA_SYEV** and **LA_SYEVD** compute all eigenvalues and, optionally,
all eigenvectors of a real symmetric matrix .

**LA_HEEV** and **LA_HEEVD** compute all eigenvalues and, optionally,
all eigenvectors of a complex Hermitian matrix .

**LA_SYEVD** and **LA_HEEVD** use a divide and conquer algorithm.
If eigenvectors are desired, they can be much faster than **LA_SYEV**
and **LA_HEEV** for large matrices but use more workspace.

Susan Blackford 2001-08-19