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Example (from Program LA_GELSY_EXAMPLE)

The results below are computed with $\epsilon = 1.19209 \times 10^{-7}$.

\begin{displaymath}
A = \left( \begin{array}{rrrr}
0 & 9 & -6 & 3 \\
-3 & 0 ...
...0 & 2 & 2 \\
-4 & 1 & 2 \\
1 & -2 & 6
\end{array} \right)
\end{displaymath}

A, B, JPVT and RCOND on entry:

\begin{displaymath}
\begin{array}{c} {\bf A} \\
\begin{array}{\vert rrrr\vert...
...vert} \hline
0 & 0 & 1 & 0 \\
\hline \end{array} \end{array} \end{displaymath}

The call:
CALL LA_GELSY( A, B, RANK, JPVT,
1.0E-5_wp ) 6.1

B, RANK and JPVT on exit:

\begin{displaymath}\hspace{-1.00 cm}
\begin{array}{c} {\bf B} \\
\begin{array...
...; 2.20431 & \;\;\; 5.33678 \\
\hline \end{array} \end{array} \end{displaymath}


\begin{displaymath}
\begin{array}{c} {\bf RANK} \\
\begin{array}{\vert c\vert}...
...vert} \hline
3 & 2 & 1 & 4 \\
\hline \end{array} \end{array} \end{displaymath}

The rank of matrix $A$ is 2.

The solution matrix is:


\begin{displaymath}X = \left( \begin{array}{lll}
\;\;\; 4.20045 \times 10^{-1} ...
...mes 10^{-1} & -5.91214 \times 10^{-3} \\
\end{array} \right). \end{displaymath}



Susan Blackford 2001-08-19