[pstricks] arrows on a curve

[Marco Daniel]

Hi,

1: you can use a loop also with postscript notation

\documentclass{minimal}
\usepackage{pstricks}
\usepackage{pstricks-add}
\begin{document}
\begin{psgraph}[labels=none,ticks=none](0,0)(-5,-1)(5,20){8cm}{8cm}
\multido{\ra=-4+0.5,\rb=-3.5+0.5}{8}{%
         \psplot[algebraic,arrows=->,arrowscale=1.5]{\ra}{\rb}{x^2}
         }
  \multido{\ra=0+0.5,\rb=0.5+0.5}{8}{%
          \psplot[algebraic,arrows=<-,arrowscale=1.5]{\ra}{\rb}{x^2}
          }
\end{psgraph}
\end{document}

2: I think. In the documentation you will find an example for including 
files


regards
Marco