Re: Stem update, rough guess.

[John W. Eaton]

On  6-Apr-2007, Daniel J Sebald wrote:

| Shai Ayal wrote:
| > On 4/6/07, John W. Eaton <address@hidden> wrote:
| > 
| >> Checking that the color is not empty is the thing to do.
| 
| OK; as it is then.
| 
| >> | Also, I don't really follow the hh, hhh, hhhh handle stuff.  My way
| >> | of thinking is that plot() should now assign that correctly if
| >> | everything is done with one plot command.  So I've put comment
| >> | characters in front of all those lines and someone else can evaluate
| >> | if that is really needed.
| >>
| >> I don't know what that is all about either.  We should probably be
| >> setting the markerfacecolor property if dofill is true, but that
| >> property is not handled in the graphics.cc file or by __go_draw_axes__
| 
| The stem.m help doesn't indicate what "fill" means.  I don't know how one 
fills 
| a stem plot.  Color in the circle?  But that is a different symbol in the 
list 
| of options.  (There is mention of "bar" in the help, maybe that is what fill 
| pertains to.)
| 
| >> yet.  I have no idea what the intent was for plotting an additional
| >> line using the axis limits.
| > 
| > 
| > The intent: If the plotted vector has both negative and positive
| > values (say sin(1:10)) this would plot a line at y=0 to show where the
| > axis zero is. Why this is important I do not know. Maybe it's a Matlab
| > compatibility thing ?
| 
| OK, yes that is this part:
| 
| #  if (find (y < 0))
| #    x_axis_range = get (gca, "xlim");
| #    hhhh = line (x_axis_range, [0, 0], "color", [0, 0, 0]);
| # endif
| 
| In gnuplot that is handled with a separate "set", and I'm guessing this axis 
| line might be a property for the matryoshka pointers.  So, what I've done in 
the 
| attached patch is use the fputs/__plot_stream__ mechanism as an illustration. 
| I've made the line half size so it doesn't stand out so.  If this makes 
sense, 
| then this can be moved into __go_draw_axes__ with some new type of property.
| 
| Now, in the examples for stem.m I see this one:
| 
| ## @example
| ## x = 1:10;
| ## y = ones (size (x))*2.*x;
| ## h = stem (x, y, "b");
| ## @end example
| ## @noindent
| ## plots 10 bars with heights from 2 to 20
| 
| Bars are certainly possible with gnuplot, but isn't "b" conflicting with the 
| plot option "blue" which is "b"?
| 
| Dan

The patch you sent seems to include changes that have already been
checked in.  Can you please sort that out and submit a new patch that
is relative to the current CVS sources?

Thanks,

jwe