only defined points plotting



> i think i am in favor of this. it should be maintained by set_plot_option
> (i.e., not a global flag). how is this going to work, exactly?

I have attached a patch for plot.lisp which implements this. As you
can see the adaptive plotter has to be modified too (for efficiency
reasons).

Use it like

 plot2d(log(sin(x)), [x,-6,6]);
 plot2d(log(sin(x)), [x,-6,6], [plot_realpart, false]);

(I haven't tested it much though).

Andrej

Attached file: plot.lisp.patch