'figure' does not accept 0 as argument

[John W. Eaton]

On  9-Mar-2008, Sergei Steshenko wrote:

| Hello All,
| 
| I've noticed this behavior:
| "
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| octave:1> figure(0)
| warning: get: invalid property `type'
| error: figure: expecting figure handle or figure number
| error: evaluating if command near line 41, column 5
| error: evaluating if command near line 39, column 3
| error: called from `figure' in file
| `/maxtor5/sergei/AppsFromScratchWD/install/octave-3.0.0/share/octave/3.0.0/m/plot/figure.m'
| octave:1> figure(1)
| octave:2>
| ".
| 
| Well, still, 0 is an integer number, so I do not understand the "figure number" part in
| "error: figure: expecting figure handle or figure number" message.

The diagnostic could be better, but it is not a bug that figure (0)
fails since the graphics handle 0 is the identifier for the special
"root figure", which is somewhat like the base object for all
graphics objects.  You can use it to set defaults for other graphics
objects, but you can't display it like other figures.

jwe