DSTEVX Example

To find the eigenvalues in the half-open interval $\left(\vphantom{0, 5}\right.$0, 5$\left.\vphantom{0, 5}\right]$, and the corresponding eigenvectors, of the symmetric tridiagonal matrix

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

Example program
Example data
Example results