DSTEVR Example

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

A = $\displaystyle \left(\vphantom{
\begin{array}{rrrr}
1 & 1 & 0 & 0 \\
1 & 4 & 2 & 0 \\
0 & 2 & 9 & 3 \\
0 & 0 & 3 & 16
\end{array} }\right.$$\displaystyle \begin{array}{rrrr}
1 & 1 & 0 & 0 \\
1 & 4 & 2 & 0 \\
0 & 2 & 9 & 3 \\
0 & 0 & 3 & 16
\end{array}$$\displaystyle \left.\vphantom{
\begin{array}{rrrr}
1 & 1 & 0 & 0 \\
1 & 4 & 2 & 0 \\
0 & 2 & 9 & 3 \\
0 & 0 & 3 & 16
\end{array} }\right)$.

Example program
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