[pstricks] a problem with \psplotDiffEqn

[Herbert Voss]

Andrzej J. Maciejewski schrieb:
> Herbert,
> in fact
> \psplotDiffEqn[arrows=->,ArrowInside=->,arrowscale=2]{0}{8}{4}{\Func}
> gives one arrow in each line joining two points. The problem appear when I
> want to optain a smooth curve and put e.g. plotpoints=100, then my curve
> consists of arrows only.
> If there is no a direct way I will try to find a solution in a different
> way.

Draw the curve twice, one with plotstyle=none.

\documentclass{article}
 \usepackage{pstricks-add}
 \begin{document}
 %
 \def\Func{ neg }
 %
 \psset{method=rk4,plotpoints=20,linecolor=blue,linewidth=0.5pt}
 \begin{pspicture}[showgrid=true](0,-0.5)(8,4)
 \psplotDiffEqn[linestyle=none,arrows=->,ArrowInside=->,arrowscale=2]{0}{8}{4}{\Func}
\psplotDiffEqn[plotpoints=100]{0}{8}{4}{\Func}
\end{pspicture}

\end{document}

Herbert