[pstricks] log/ln in radial context for circular sliderule

[Carsten Vogel (orphaned)]

превиет!
I am working myself through the magic of sliderules right now and want 
to spend some thoughts on rebuilding one. I think that labeling should 
be done precisely therefore by PSTricks (or maybe something else?).

Now I started to map 1..10 to 0..360 of a circle to draw tickmarks in a 
log-fashion. My idea is (1st iteration):
$f(x)=-\frac{\ln(x)\times360}{\ln(10)}$  $D_f=[0..10]\subset\mathbf{N}$

So where do I go wrong?

%% /lograd \i\space ln -360 mul 10 ln div def

Even a "simple number" isnt doing it and throwing "! Bad number: `lograd´."

TIA,
Carsten


\documentclass{article}
\usepackage{pstricks,multido}

\SpecialCoor

\begin{document}
\multido{\i=0+1}{10}{
\pstVerb{%
	/lograd 10 def
}
	\psline(4.9; lograd)(5.2; lograd)
}
\end{document}