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Example 2 (from Program LA_PBSV_EXAMPLE)

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

\begin{displaymath}
A = \left( \begin{array}{rrrrrrr}
16 & 3 & 2 & 1 \\
3 & ...
...& 111 \\
31 & 62 & 93 \\
22 & 44 & 66
\end{array} \right).
\end{displaymath}

AB and B on entry:

\begin{displaymath}
\begin{array}{c} {\bf AB} \\
\begin{array}{\vert rrrrrrr\...
...& 62 & 93 \\
22 & 44 & 66 \\
\hline \end{array} \end{array}\end{displaymath}

The call:
CALL LA_PBSV( AB, B, INFO=
INFO )

AB, B and INFO on exit:

\begin{displaymath}\begin{array}{c} {\bf AB} \\
\begin{array}{\vert@{\hspace{2m...
...5.24475 & 5.05429 & 4.64073 \\ \hline
\end{array} \end{array} \end{displaymath}


\begin{displaymath}\begin{array}{cc} {\bf AB} \\
\begin{array}{l\vert} \hline
...
...} \hspace{0.50 cm} \begin{array}{c} {\bf INFO} = 0 \end{array} \end{displaymath}

Matrices $U$ and $X$, where $A\,=U^TU$ and $X$ is the solution of the system $ A\,X = B $:

\begin{displaymath}U = \left(
\begin{array}{@{\hspace{1mm}}l@{\hspace{1mm}}l@{\h...
...{-1} \\
& & & & & 4.64073 \\
& & & & & \end{array} \right. \end{displaymath}


\begin{displaymath}\left. \begin{array}{l}
\\
\\
\\
1.90667 \times 10^{-1...
... 3.00000 \\
1.00000 & 2.00000 & 3.00000 \end{array} \right). \end{displaymath}



Susan Blackford 2001-08-19