# Is there a formula to setup the smallest rectangle enclosing a PSTricks grid and its labels?

I want to minimize the size of the red rectangle enclosing a PSTricks grid and its labels. How to do this?

\documentclass{minimal}
\usepackage{pstricks}
\newpsstyle{gridstyle}{gridlabels=5pt}
\psset{style=gridstyle}
\pagestyle{empty}

\begin{document}
\psframebox[linewidth=0.5pt,linecolor=red,framesep=5.5pt]{%
\begin{pspicture}[showgrid](3,3)
\pscircle[fillstyle=solid,fillcolor=red,opacity=0.2](1.5,1.5){1.5}
\end{pspicture}}
\end{document}
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