Why does the timer object fail when I run MATLAB remotely through a text window?

I use telnet or ssh to log into a remote UNIX/Linux machine and run MATLAB on that machine. I only have a text-based window, and do not have X11 forwarding enabled for this connection (or I do not have an X-server running on my local machine).

When I run MATLAB, I see the following warning:

 Warning: Unable to open display , MATLAB is starting without a display.

   You will not be able to display graphics on the screen.

While running MATLAB, issuing a command such as FIGURE does not produce any output on the screen.

I then create a timer object and start it as shown below:

a=1;

t=timer('TimerFcn','a=5','Period',2,'ExecutionMode', 'fixedRate');

start(t)

The "TimerFcn" is never executed as I can verify by checking the value of the variable "a" at any point after the timer has been started. In other words, the following command typed at the MATLAB prompt:

a

will produce

 a =

      1

whereas it should return a value of 5 for "a", since I expect the "TimerFcn" to execute at least once at this point.

Answer 1

[MathWorks Support Team]

This enhancement request has been incorporated in Release 14 Service Pack 3 (R14SP3).

For previous product releases, the ability to use the timer object and other XEvent based objects in MATLAB is not available when running MATLAB remotely in a text window with no X11 forwarding.

The workaround is to run MATLAB in an environment where the Java Virtual Machine (JVM) is available on the remote/host machine, and the local machine is running an X-server application. X11 forwarding must also be enabled for the connection to allow XEvent-based objects to work properly.