DSYEVR Example

To find the eigenvalues with indices in the range $ \left[\vphantom{2, 3}\right.$2, 3$ \left.\vphantom{2, 3}\right]$, and the corresponding eigenvectors, of the symmetric matrix

A = $\displaystyle \left(\vphantom{
\begin{array}{rrrr}
1 & 2 & 3 & 4 \\
2 & 2 & 3 & 4 \\
3 & 3 & 3 & 4 \\
4 & 4 & 4 & 4
\end{array} }\right.$$\displaystyle \begin{array}{rrrr}
1 & 2 & 3 & 4 \\
2 & 2 & 3 & 4 \\
3 & 3 & 3 & 4 \\
4 & 4 & 4 & 4
\end{array}$$\displaystyle \left.\vphantom{
\begin{array}{rrrr}
1 & 2 & 3 & 4 \\
2 & 2 & 3 & 4 \\
3 & 3 & 3 & 4 \\
4 & 4 & 4 & 4
\end{array} }\right)$.

Information on required and provided workspace is also output.

Example program
Example data
Example results