[pstricks] arcangle=nonconstant?

[Bob Tennent]

 >|> But either way, I need to do computation with numbers known to LaTeX,
 >|> not just constants (180, 2, etc.). Suppose I have the angle I want in a
 >|> TeX counter; how do I pass that number to \ncarc (or to Postscript)?
 >|
 >|\newcounter{mycounter}
 >|\setcounter{mycounter}{90}
 >|
 >|\pnode(0,0){A}\pnode(11,0){B}
 >|\ncarc[arcangleA=\themycounter]{A}{B}

Thanks. Is there a way to make this work with \SpecialCoor?

\newcounter{xx}
\newcounter{yy}
\setcounter{xx}{5}
\setcounter{yy}{3}

\pnode(0,0){A}\pnode(10,0){B}
\SpecialCoor
\ncarc[arcangle=(\thexx,\theyy)]{A}{B}


Package xkeyval Error: `3)' undefined in families `,pstricks-add'.