Re: Contour plots

[Hans-Bernhard B. <br...@ph...>]

Harald Harders wrote:

> Hans-Bernhard, what do you think about my suggestion that the user
> could provide a curve in x-y space (parametric function or data
> points). The labels can then be placed where the given curve and the
> contour lines intersect.
> 
> A syntax could be as follows:
> 
> set cntrparam labels along 3*t, 3*t**2
> set cntrparam labels along 'filename.dat' using 1:2

IMHO, that's exactly the right direction in general.  What I'm worrying 
about are the details.  Like

1) One locus curve only, or several?
2) A label at every intersection, or only every n-th?
3) How to specify the curve[s] (abusing variable 't' feels like almost
certainly the wrong idea...)

I guess while at it, the entire command handling of 'set contour'
would have to undergo a review: 'set clabel' is a dangerously ill-named,
hard-to-find option; 'set contour' and 'set cntrparam' don't really 
deserve being separate commands; and there probably should be a 
"contour axis" with all the usual capabilities (so the contours to be 
used would be selected through 'set ctics' and 'set crange', and labels 
by the difference between minor/major ctics, text to be printed by 'set 
cformat', ...) used by the contouring code.  This would take a large 
part of the load off the shoulders of 'set cntrparam', and possibly make 
it redundant, so the remaining job can be done by 'set contour' alone.