MATLAB Central Newsreader - Event queue

Event queue

Chris Rodgers — Thu, 14 Feb 2008 12:36:12 -0500

Hi,

A couple of event queue related items...

1) Is it possible to display the current Matlab event queue for
debugging purposes?

2) If I have a timer

t = timer

and then inside another routine, I set t.Running = 'off', will the
events for timer t that are already in the event queue be deleted, or
may the timer still end up running its callback after the long routine
completes?

Thanks,

Chris.

Re: Event queue

roberson@ibd.nrc-cnrc.gc.ca (Walter Roberson) — Thu, 14 Feb 2008 17:09:05 -0500

In article <fp1cjs$8rl$2@frank-exchange-of-views.oucs.ox.ac.uk>,
Chris Rodgers <rodgers@physchem.NOSPAMox.aREMOVEc.uk> wrote:

>A couple of event queue related items...

>1) Is it possible to display the current Matlab event queue for
>debugging purposes?

I don't know, but I see that someone has coded FlushEvents.m
to remove all events of a given kind from the Matlab queue.
Usually if you have enough access to the queue to be able to
examine an event to be able to flush it, you would have enough
access to be able to display it, but this is not always true;
I suggest checking out the code (www.koders.com)

>2) If I have a timer

>t = timer

>and then inside another routine, I set t.Running = 'off', will the
>events for timer t that are already in the event queue be deleted, or
>may the timer still end up running its callback after the long routine
>completes?

According to the documentation for timer(), the Running field
is read-only.
--
"I will not approve any plan which is based on the old principle
of build now and repair later." -- Walter Hickle

Re: Event queue

Ryan Ollos — Fri, 28 Nov 2008 23:20:04 -0500

roberson@ibd.nrc-cnrc.gc.ca (Walter Roberson) wrote in message <fp1sjh$9iu$1@canopus.cc.umanitoba.ca>...
> In article <fp1cjs$8rl$2@frank-exchange-of-views.oucs.ox.ac.uk>,
> Chris Rodgers <rodgers@physchem.NOSPAMox.aREMOVEc.uk> wrote:
>
> >A couple of event queue related items...
>
> >1) Is it possible to display the current Matlab event queue for
> >debugging purposes?
>
> I don't know, but I see that someone has coded FlushEvents.m
> to remove all events of a given kind from the Matlab queue.
> Usually if you have enough access to the queue to be able to
> examine an event to be able to flush it, you would have enough
> access to be able to display it, but this is not always true;
> I suggest checking out the code (www.koders.com)

Hello Walter,

I have the same question as Chris. I have not been able to find the FlushEvents.m that you refer to, either on the FEX or koders.com. Could you post a direct link?

Re: Event queue

Walter Roberson — Mon, 01 Dec 2008 22:57:21 -0500

Ryan Ollos wrote:
> roberson@ibd.nrc-cnrc.gc.ca (Walter Roberson) wrote in message <fp1sjh$9iu$1@canopus.cc.umanitoba.ca>...

>> I don't know, but I see that someone has coded FlushEvents.m
>> to remove all events of a given kind from the Matlab queue.

> I have not been able to find the FlushEvents.m that you refer to,

What I was able to find this time was a part of (the old version of?) psych tools,
and reading around a bit it appeared to call a mex routine, and on MS Windows apparently
that mex routine is restricted to removing keyboard presses (with more functionality under
Mac OS.) Not what I'd call a real interface to the Matlab event queue :(

(Note: I have made no attempt myself to figure out how the Matlab event queue operates.)

--
.signature note: I am now avoiding replying to unclear or ambiguous postings.
Please review questions before posting them. Be specific. Use examples of what you mean,
of what you don't mean. Specify boundary conditions, and data classes and value
relationships -- what if we scrambled your data or used -Inf, NaN, or complex(rand,rand)?