Need some help using plot 2d



> 
> So the question is: How can I choose what XY numbers should be
> displayed for each axis? (Half numbers would be a nice bonus)
> I can live with Y skipping a couple numbers, but I really need to be
> able to control X.

You have to add some gnuplot commands in the "gnuplot_preamble" part:

wxplot2d(2*x-1, [x,-5,5],
[gnuplot_preamble, "set grid;set xtics norotate border -5.0,1.0,5.0"])$


> 
> Another question I have is: Is there a way to highlight where X meets
> Y in the graph?

For example, if you want to highlight point (-2, 3):

wxplot2d([2*x-1,[discrete, [[-2,3]]]], [x,-5,5], [style, lines, points],
  [gnuplot_preamble, "set grid;set xtics norotate border -5,1,5"] )$


The corresponding draw versions are:

wxdraw2d(
   grid = true,
   explicit(2*x-1,x,-5,5),
   xtics = [-5,1,5]);

and

wxdraw2d(
   grid = true,
   explicit(2*x-1,x,-5,5),
   xtics = [-5,1,5],
   point_type = circle,
   point_size = 2,
   points([[2,3]]) );


In more info, type

?? tics



-- 
Mario