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Re: Quit versus Clear["Global`*"]

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  • Subject: [mg121251] Re: Quit versus Clear["Global`*"]
  • From: "tenons at" <tenons at>
  • Date: Tue, 6 Sep 2011 03:57:01 -0400 (EDT)
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  • References: <j3t5ga$58h$> <j3vc1k$ejo$>

On Sep 4, 4:14 am, David Bailey <d... at> wrote:
> On 03/09/2011 13:10, Themis Matsoukas wrote:> What is the difference between quitting the kernel and executing Clear["Global`*"]?
> > Is there a command to quit the kernel, instead of selecting Quit/Local from there Evaluate menu?
> > Thanks
> Quit[] will quit the kernel.
> Obviously Clear["Global`*"] would not clear information that might end
> up in other contexts, whereas Quit[] will clear everything.
> I never clear the global context - I just quit the kernel one way or
> another. Restarting the kernel used to be rather slow, but with the
> speed of a modern PC, there really doesn't seem much point doing
> anything else unless you specifically wish to preserve some information
> that is not in Global`.
> I tend to quit the kernel quite a lot - e.g. between successive runs of
> a program - why risk the confusion that can arise when two function
> definitions end up coexisting!
> David Bailey

I agree whole-heartedly with this post.  I've found it the only way
to stay out of trouble.

I have a related problem that I hope I can get some suggestions for.

GIF.exe has a memory leak (reported previously, acknowledged and is on
someone's todo list at Wolfram, hopefully) which makes a certain set
evaluations (which use ExportString[#,"GIF"]& extensively) unstable.
(i.e., MathKernel crashes randomly and unceremoniously, or worse).

What I would like to do is divide the set of evaluations into
segments, run them successively quitting the MathKernel after each,
and then restarting on the next segment.  The Quit[] clears out the
buildup in GIF.exe. Obviously I can do this by babysitting and
restarting each segment by hand (which I do, at approximately 15
minute intervals, painfully wasting time).

[I've tried many things including Uninstall["path/GIF.exe"] 'ing
periodically and escaping to the shell to kill the process.  Neither
improves stability. ]

How can I carry this out automatically?

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