Re: [ferret_users] white contours

["william s. kessler" <william.s.kessler@xxxxxxxx>]

Note that this method will let you make thick "white" contour lines,  
in the example here by contouring with pen 18 instead of 6.

If these techniques don't work, the brute-force way to deal with this  
is to edit the postscript. Choose an unused color as in this example,  
but don't redefine it in Ferret. Instead, make the postscript; then  
search the mail archives for "pen color and postscript". There are  
several discussions of this over the years but the one from 12 Jan  
2007 explains how to force-fix the problem by editing the postscript.

Billy K

On 3Oct 2007, at 2:44 PM, william s. kessler wrote:

> Yes, this happens occasionally with white lines. I assume it is a  
> bug somewhere. A *possible* fix: redefine one of the colors to  
> something that is very near white. Sometimes this will avoid the  
> problem. Choose a pen number that is otherwise unused:
>
> ppl color,6,99,99,99   ! pen 6 is otherwise not used
> contour/over/color=6 .....
>
> Remember that if the PPL COLOR command is used to redefine a  
> particular color more than once in a plot, unpredictable results  
> can occur. There are some examples of this behavior in the user  
> discussions from the last century, I think.
>
> Billy K
>
>
>
>
> On 3Oct 2007, at 1:46 PM, nguyen@xxxxxxxxxx wrote:
>
> > Hi ferreter
> >
> > I have a figure with white contour. When I convert it to a postscript
> > file, this following message appear and all the contours/shading  
> > following
> > the white contour, including the white contour are not appeared on  
> > the .ps
> > file. Any idea?
> >
> > > ERROR: /typecheck in --aload--
> > > Operand stack:
> > >     --nostringval--
> > > Execution stack:
> > >     %interp_exit   .runexec2   --nostringval--   --nostringval--
> > > --nostringval--   2   %stopped_push   --nostringval--   -- 
> > > nostringval--
> > >    --nostringval--   false   1   %stopped_push   1   3   % 
> > > oparray_pop
> > > 1   3   %oparray_pop   1   3   %oparray_pop   1   3   %oparray_pop
> > > .runexec2   --nostringval--   --nostringval--   --nostringval--   2
> > > %stopped_push   --nostringval--   --nostringval--
> > > Dictionary stack:
> > >     --dict:1123/1686(ro)(G)--   --dict:0/20(G)--   --dict:124/200 
> > > (L)--
> > > Current allocation mode is local
> > > Current file position is 188694
> > > ESP Ghostscript 815.04: Unrecoverable error, exit code 1
> > Thanks
> > Hanh