meshz, and leading axis handles to mesh, meshc and surface

[John W. Eaton]

On 28-Nov-2007, David Bateman wrote:

| This patch adds the meshz function and allows an axis handle to be the
| leading argument for the mesh, meshc and surface functions. It only
| needed to be implemented in surface for mesh and meshc, though meshz
| needed to implement the handle code as well as meshz modifies the x, y,
| and z values before handing them to mesh and so needs to know if the
| leading arg is a handle.

| 2007-11-27  David Bateman  <address@hidden>
| 
|       * plot/meshz.m: New function.
|       * plot/Makefile.in (SOURCES): Add it to teh sources.
|       * plot/surface.m: Allow surface to accept an axis handle as the
|       first argument.
|       * plot/meshc.m: Extract z from the the surface object rather than
|       varargin so that we can rely on code in surface to treat leading
|       axis handles.

I checked in these changes.

| There are quite a few other functions that don't allow an axis handle as
| the first argument and should. These include errorbar, loglogerr,
| loglog, polar, semilogx, semilogyerr, semilogy where the code to do it
| is in __plt_get_axis_arg__ but is disabled, and stem where no code
| exists to do it.
| 
| Maybe all of the functions that can accept an axis handle as the first
| argument should be adapted to use __plt_get_axis_arg__, which perhaps
| the code in __plt_get_axis_arg__ allowing the unwind_protect code block
| to restore the axis. Given that I've been adding similar code in all of
| the individual routines this seems to be a non trivial task though
| simple task. So should it be done before 3.0?

Sure, if you want to do it, I think it would be great if we used a
consistent method in all the functions that do this.

Thanks,

jwe