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Example 1 (from Program LA_POSV_EXAMPLE)


\begin{displaymath}
A = \left( \begin{array}{rrrrr}
38 & 3 & 4 & 6 & 5 \\
3 ...
... \\
80 & 160 & 240 \\
102 & 204 & 306 \end{array} \right).
\end{displaymath}

Arrays ${\bf A}$ and ${\bf B}$ on entry:

\begin{displaymath}
\hspace{-1.00 cm}
\begin{array}{c} {\bf A} \\
\begin{arr...
...60 & 240 \\
102 & 204 & 306 \\ \hline \end{array} \end{array}\end{displaymath}

Elements marked $\ast$ are not used by the routine. The call:
CALL LA_POSV( A, B )

Arrays A and B on exit:


\begin{displaymath}
\begin{array}{c} {\bf A} \\
\begin{array}{\vert lllll\ver...
...\;\;\;\;\;\; \ast & 8.40898 \\
\hline \end{array} \end{array}\end{displaymath}


\begin{displaymath}
\begin{array}{c} {\bf B} \\
\begin{array}{\vert rrr\vert}...
...1.00000 & 2.00000 & 3.00000 \\
\hline \end{array} \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}{lllll}
6.16441 & 4.86664 \times 10...
...\; 7.35919 & 1.13404 \\
& & & & 8.40898
\end{array} \right)
\end{displaymath}


\begin{displaymath}
X = \left( \begin{array}{rrr}
1.00000 & 2.00000 & 3.00000 ...
...3.00000 \\
1.00000 & 2.00000 & 3.00000
\end{array} \right).
\end{displaymath}



Susan Blackford 2001-08-19