[pstricks] tangential vector

[Herbert Voss]

Doris Wagner schrieb:

> I have a graph which shows a trajectory (e.g. polynomial) of a  
> physical object and I want to draw the tangent vector. the problem  
> with \psplotTangent is that it goes in two directions from one point  
> of the graph. is there a possibility to get only half of it?

http://voss.homedns.org/packages/pstricks-add/pstricks-add.tex
knows a star version \psPlotTangent*, which plots only a line
into the positive x direction.

this version pf pstricks-add.tex needs also the pst-fp.tex,
also available from http://voss.homedns.org/packages/pstricks-add/


Herbert