pathological plot




I don't read sloop code, but I speculate that draw2d (defined in plot.lisp)
does a adaptive evaluation of the function -- presumably where the function
changes rapidly, it is evaluated on a finer (and finer) grid.  Does
plot2d (or friends) get stuck in a loop taking too fine a grid?

Actually, I wonder if we'd be better off developing a better gnuplot
interface
for Maxima than improving plot.lisp --  Do we have the resources to write
really good graphical code from scratch?  The mygnuplot function
[see describe("system") ] could be improved without a great deal of
work -- I've hacked on it a bit so that it works better for me.

Or maybe somebody could write an interface to something other than gnuplot?


Barton


>>>>> "Rich" == Rich Drewes <drewes@interstice.com> writes:

    Rich> Consider this Maxima input:

    Rich> f(x):=(7-500*x)/(25 * x);
    Rich> plot2d(f(x), [x, .008, .012], [y, 2, 16]);

    Rich> The plot takes upwards of 20 minutes to appear on a reasonably
    fast
    Rich> system.  Something pathological seems to be going on with
    certain
    Rich> domains for the plot of many simple functions.  Also, when the
    plot
    Rich> finally does appear, the y axis doesn't seem to be present (even
    when
    Rich> the plot is moved around the window) and the x axis doesn't have
    Rich> reasonable tick marks.