**LA_SYEVR** / **LA_HEEVR** compute selected eigenvalues and,
optionally, the corresponding
eigenvectors of a real symmetric/complex Hermitian matrix .
Eigenvalues and eigenvectors can be selected by specifying
either a range of values or a range of indices for the desired
eigenvalues.

**LA_SYEVR** and **LA_HEEVR** use a relatively robust
representation (RRR)
algorithm. It is usually the fastest algorithm of all
and uses the least workspace.

Susan Blackford 2001-08-19