DSYEV Example

To find all the eigenvalues and eigenvectors of the symmetric matrix

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

together with approximate error bounds for the computed eigenvalues and eigenvectors.

Example program
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Example results