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

Information on required and provided workspace is also output.

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