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Example (from Program LA_PTSV_EXAMPLE)

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

\begin{displaymath}
A = \left( \begin{array}{rrrrr}
7 & 3 \\
3 & 7 & 3 \\
...
...6 & 39 \\
13 & 26 & 39 \\
10 & 20 & 30 \end{array} \right)
\end{displaymath}

Arrays ${\bf D}$, ${\bf E}$ and ${\bf B}$ on entry:

\begin{displaymath}
\begin{array}{c} {\bf {\bf D}} \\
\begin{array}{\vert r\v...
...3 & 26 & 39 \\
10 & 20 & 30 \\ \hline \end{array} \end{array}\end{displaymath}

The call:
CALL LA_PTSV( D, E, B, INFO )

${\bf D}$, ${\bf E}$, ${\bf B}$ and ${\bf INFO}$ on exit:

\begin{displaymath}
\begin{array}{c} {\bf D} \\
\begin{array}{\vert l\vert} \...
...00 \\ \hline
\end{array} \end{array} \ \ \ \
{\bf INFO} = 0
\end{displaymath}

Matrices $L$ and $X$, where $A = L\,D\,L^H$ and $X$ is the solution of the system $ A\,X = B $:

\begin{displaymath}
L = \left( \begin{array}{lllll}
7.00000 \\
4.28571 \time...
...
& & & 5.61691 \times 10^{-1} & 5.31493
\end{array} \right)
\end{displaymath}


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



Susan Blackford 2001-08-19