[pstricks] Opening a data file with postscript

[Herbert Voss]

Am 22.09.24 um 23:15 schrieb Poul Riis:
> Even if it triggers an error message from ps2pdf the following program 
> produces a perfect .ps file - and I can save it as a .pdf file with 
> the ghostviewer!
> Do you think it is possible to make ps2pdf work with some options?
> It seems impossible to reuse the matrix in another \pstverb or any 
> other pstricks command. Do you know why? And is there a workaround?
> Is there a way to calculate xscale and yscale from the psgraph 
> definitions?
> Well, I know this is not very important because I can just use 
> datatool instead but I'm crazy enough.... - and I would like to 
> understand the reasons for the problems - obviously it is not true 
> when it is said that postscript does not allow access to external files...

\pstverb -> outside pspicture
\pstVerb -> inside pspicture


\documentclass[a4paper,14pt]{article}
\usepackage[x11names]{xcolor}
\usepackage{pstricks-add}


\begin{document}
     ~
\makeatletter
     \begin{psgraph}[axesstyle=frame,ticksize=0 -3pt,subticks=5,
         Dx=5,Dy=200,yAxisLabel={Velocity (km/s)},
         xAxisLabel={Distance (Mpc)},llx=-1cm,xAxisLabelPos={6cm,-1 cm},
         yAxisLabelPos={-1.5cm,3cm}](0,0)(30,1200){12cm}{8cm}%
         \pstVerb{(/tmp/hubblepsarrays.txt) run
             currentpoint translate
             /ndat 18 def
             /xscale {\pst at number\psxunit mul} def
             /yscale {\pst at number\psyunit mul} def
             30 xscale 1200 yscale 5 0 360 arc 1 0 0 setrgbcolor fill stroke
             0 1 0.5 setrgbcolor
             0 1 ndat {
                 /ii exch def
                 xhubble ii get xscale
                 yhubble ii get yscale
                 2 0 360 arc fill stroke} for
             1 0 0 setrgbcolor
             0 1 ndat {
                 /ii exch def
                 xstel ii get xscale
                 ystel ii get yscale
                 2 0 360 arc fill stroke} for
                 0 0 1 setrgbcolor
                 [3 3] 0 setdash
             0 1 ndat {
                 /ii exch def
                 xhubble ii get xscale
                 yhubble ii get yscale
                 moveto
                 xstel ii get xscale
                 ystel ii get yscale
                 lineto stroke
             } for
             %showpage
             }
         \psline(0,0)(0,-400)(30,-400)(30,0)
         %\psline(!0 0)(!xhubble 5 get yhubble 5 get)
     \end{psgraph}
\end{document}


Herbert