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Examples

The packed storage scheme is illustrated by the following example, where $n = 4$:

\begin{displaymath}
A = \left( \begin{array}{rrrr}
a_{11} & a_{12} & a_{13} & a...
...{34} \\
a_{41} & a_{42} & a_{43} & a_{44} \end{array} \right)
\end{displaymath}

where $a_{ij} = a_{ji} \;\; \mbox{for} \;\; i,j = 1, \cdots, 4.$

Packed storage of the upper triangle of $A$:

\begin{displaymath}
\begin{array}{c} {\bf AP} \\
\begin{array}{\vert rrrrrrrr...
...} &
a_{24} & a_{34} & a_{44} \\ \hline \end{array} \end{array}\end{displaymath}

Packed storage of the lower triangle of $A$:

\begin{displaymath}
\begin{array}{c} {\bf AP} \\
\begin{array}{\vert rrrrrrrr...
...} &
a_{33} & a_{43} & a_{44} \\ \hline \end{array} \end{array}\end{displaymath}



Subsections

Susan Blackford 2001-08-19