Re: How to find if an object contains another

[Pavel Romashkin <promashkin(at)cmdl.noaa.gov>]

I would try

if obj_valid((model->get(/all,isa='idlgrsurface'))[0]) then $
	print,'Has one or more surface' $
else $
	print,'Has no surfaces'

or, better yet, because it provides a useful list as the result:

surf_list = model->get(/all,isa='idlgrsurface', count=n_surfs)
if n_surfs gt 0 then .....

Same thing about finding out if GetbyName returned a valid object.
Cheers,
Pavel

Dave Greenwood wrote:
> 
> How do I determine if an object "contains" another one?
> 
> For example, I can create a model object and add a surface object or
> a plot object.  Given that model object, how would I find out whether
> or not a surface object has been added?
> 
> The best I've come up with is something like:
> 
>   xx = model->get(/all,isa='idlgrsurface')
>   s = size(xx)
>   if s[1] eq 11 then $
>        print,'Has one or more surface' $
>   else $
>        print,'Has no surfaces'
> 
> Surely there's a simpler way?
> 
> A related question is: how do I test if an object pointer (returned by
> the GetByName method, for example) is null?
> 
> Thanks,
> Dave
> --------------
> Dave Greenwood                Email: Greenwoodde@ORNL.GOV
> Oak Ridge National Lab        %STD-W-DISCLAIMER, I only speak for myself