# [pstricks] Vertical \ncarcbox in \psmatrix

Arne Hallam ahallam at iastate.edu
Sun Mar 5 03:40:34 CET 2006

I am wanting to demonstrate how to construct submatrices and am doing fine
with horizontal boxes to show row inclusion but get a circle around the
first vertical node instead of a vertical box.

\documentclass{report}
\usepackage{pstricks,pst-plot}
\usepackage{pst-node}
\usepackage{amsmath}
\SpecialCoor
\begin{document}

$$A(\{1,3\},\{1,3\})~=~\left(\raisebox{-3.0ex}{ \begin{psmatrix}[rowsep=3pt,colsep=10pt] 3 &4&7 \\ 2&5& 2 \\ 1&0&4 \end{psmatrix}} \right) \ncarcbox[nodesep=.1,boxsize=.25,linearc=0,linestyle=dashed,linecolor=green]{1,3}{3,3} \ncarcbox[nodesep=.15,boxsize=.25,linearc=0,arcangle=0.001, linestyle=dashed,linecolor=blue]{1,1}{1,3} \ncarcbox[nodesep=.15,boxsize=.25,linearc=0,arcangle=0.001,linestyle=dashed,linecolor=blue]{3,1}{3,3}$$

\end{document}