MATLAB Central Newsreader - Clearing drawn lines from a figure window

Clearing drawn lines from a figure window

Patrick — Mon, 09 Mar 2009 19:20:17 -0400

Is there any way to clear lines drawn with the line() command from a figure window? clear() doesn't seem to work. Clearing the entire figure resets the axes to defaults, and its an image window where you don't want axes. I'm not sure how to redraw the image though if thats the only way to do it I will need a ay to redraw it quickly.

Re: Clearing drawn lines from a figure window

Ashish Uthama — Mon, 09 Mar 2009 19:41:42 -0400

On Mon, 09 Mar 2009 15:20:17 -0400, Patrick <praphael@bcm.tmc.edu> wrote:

> Is there any way to clear lines drawn with the line() command from a
> figure window? clear() doesn't seem to work. Clearing the entire
> figure resets the axes to defaults, and its an image window where you
> don't want axes. I'm not sure how to redraw the image though if thats
> the only way to do it I will need a ay to redraw it quickly.

help line
...
LINE returns a column vector of handles to LINE objects,
one handle per line. LINEs are children of AXES objects.
...

You can delete this handle to remove the line from the figure.

lh=line(<...>)
%use the below when you want to delete the line
delete(lh)

If you cant/dont want to do the above, you could use the FINDOBJ to search
for the line object (tricky if you have multiple lines). This is just to
let you know of an alternative.. I would recommend using the first
approach.

Re: Clearing drawn lines from a figure window

Adam — Mon, 09 Mar 2009 19:49:01 -0400

"Patrick " <praphael@bcm.tmc.edu> wrote in message <gp3q5h$8te$1@fred.mathworks.com>...
> Is there any way to clear lines drawn with the line() command from a figure window? clear() doesn't seem to work. Clearing the entire figure resets the axes to defaults, and its an image window where you don't want axes. I'm not sure how to redraw the image though if thats the only way to do it I will need a ay to redraw it quickly.

one way
hLine = line([1 1], [0 0]); % draw line

delete(hLine) % delete line

If you're going to reuse the line later this may be preferable
set(hline, 'XData', [], 'YData', [])

If you need to update the figure
drawnow()

~Adam

Re: Clearing drawn lines from a figure window

KYAW KYAW — Thu, 10 Nov 2011 09:54:28 -0500

Dear Patrick,

Thank you for your clearing ways and I am looking for to remove some segments of the line only.
How should and please advise me.

Thanks and best regards
Kyaw

"Adam" wrote in message <gp3rrd$2ka$1@fred.mathworks.com>...
> "Patrick " <praphael@bcm.tmc.edu> wrote in message <gp3q5h$8te$1@fred.mathworks.com>...
> > Is there any way to clear lines drawn with the line() command from a figure window? clear() doesn't seem to work. Clearing the entire figure resets the axes to defaults, and its an image window where you don't want axes. I'm not sure how to redraw the image though if thats the only way to do it I will need a ay to redraw it quickly.
>
> one way
> hLine = line([1 1], [0 0]); % draw line
>
> delete(hLine) % delete line
>
> If you're going to reuse the line later this may be preferable
> set(hline, 'XData', [], 'YData', [])
>
> If you need to update the figure
> drawnow()
>
> ~Adam