MATLAB Answers

Is it possible to programmatically check whether MATLAB has been started with the "-nodisplay" option?

93 views (last 30 days)
I have a program that needs to behave differently depending on whether MATLAB has a display or not. However, I cannot determine a way to programmatically check this.
The reason I need to do this is that I sometimes start MATLAB in batch mode from a shell script, for testing my programs.

Accepted Answer

MathWorks Support Team
MathWorks Support Team on 18 Oct 2013
The ability to programmatically check whether MATLAB has a display is not available in MATLAB 7.6 (R2008a).
As a workaround, you can do one of the following:
1. Manually set or unset an environment variable in your shell script that launches MATLAB, so you can query it from inside MATLAB. For instance, setting the ISDISPLAY environment variable in your shell script before launching MATLAB:
setenv ISDISPLAY no
matlab -r "foo; quit"
(here shown with C Shell syntax), means that the MATLAB command
getenv('ISDISPLAY')
will return the string 'no' in any MATLAB processes that are spawned from this shell.
2. Query the "ScreenSize" property of the root object inside MATLAB:
get(0, 'ScreenSize')
When there is no display, this returns [1 1 1 1] instead of an actual screen size. 
Note that this will only work in releases prior to R2014b.

  0 Comments

Sign in to comment.

More Answers (3)

Paul Macey
Paul Macey on 26 Jan 2016
You may want usejava:
usejava('desktop')
This returns false for an instance of MATLAB started with -nodisplay option. I used this for a subroutine using the parallel processing toolbox, where I called a function in a parfor loop that had an error check with a msgbox and uiwait.

  0 Comments

Sign in to comment.



Jasper
Jasper on 6 Aug 2015
get(0, 'ScreenSize') % does not work in Matlab 2015a
On Matlab 2015a this will give just normal screen coordinates even when I called Matlab with the -nodisplay option.
Instead, I found a good stackoverflow topic on this question:
Summary:
if usejava('jvm') && ~feature('ShowFigureWindows')
%# use text-based alternative (input)
else
%# use GUI dialogs (questdlg)
end

  0 Comments

Sign in to comment.

Products

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!