[pstricks] Graphing function containing a parameter

[Jean-Claude Dehaes]

I tried the code and it works except if I use the latest version of pstricks-add. Then I get the message

 
 Package xkeyval Error: `hatchwidthinc' undefined in families `,pstricks-add'

The list of files in this case is

 article.cls    2004/02/16 v1.4f Standard LaTeX document class
  size10.clo    2004/02/16 v1.4f Standard LaTeX file (size option)
pstricks-add.sty    2005/03/03 package wrapper for pstricks-add.tex (hv)
pstricks.sty    2005/06/02 v0.23 LaTeX wrapper for `PSTricks' (RN,HV)
pstricks.tex    2005/09/08 v1.11 `PSTricks' (tvz)
  xcolor.sty    2005/06/06 v2.03 LaTeX color extensions (UK)
   color.cfg    2001/08/31 v1.1 color configuration of teTeX/TeXLive
   dvips.def    1999/02/16 v3.0i Driver-dependant file (DPC,SPQR)
pstricks-add.tex    2005/09/17 v2.62 `PSTricks-add' (hv)
pst-xkey.tex    2005/02/22 v1.5 PSTricks specialization of xkeyval (HA)
 xkeyval.sty    2005/07/10 v2.5c package option processing (HA)
 xkeyval.tex    2005/07/10 v2.5c key=value parser (HA)


Jean-Claude