DSPEV Example

To find all the eigenvalues 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)$,

together with an approximate error bound for the computed eigenvalues.

Example program
Example data
Example results