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

  • To: mathgroup at smc.vnet.net
  • Subject: [mg121292] Re: Quit versus Clear["Global`*"]
  • From: "Kevin J. McCann" <Kevin.McCann at umbc.edu>
  • Date: Wed, 7 Sep 2011 05:42:13 -0400 (EDT)
  • Delivered-to: l-mathgroup@mail-archive0.wolfram.com
  • References: <201109042206.SAA21533@smc.vnet.net> <j42b3a$rrv$1@smc.vnet.net> <j44k71$94u$1@smc.vnet.net>

Actually the code was just an example. I teach a class in Mathematica, 
and I would like the students to put a Quit at the top of each homework 
they turn in; so, then I can just select all and execute. The Quit 
would, of course, wipe out all previously defined things, so we start 
with a clean slate. Apparently, though, this won't work for the 
aforementioned reasons.

Kevin

On 9/6/2011 4:04 AM, DrMajorBob wrote:
> OK, putting it in a separate cell didn't help, but if you Quit while
> evaluating initialization cells... you'll stop evaluating them. (Not so
> surprising, really.)
>
> So instead of Quit, add Clear and ClearAll for everything that needs it.
> In the code of your example, there's nothing that needs it.
>
> Whenever I define a function that could EVER need Clear, I precede that
> definition with Clear. To start all over, I can go to the menus and select
> Evaluate>Evaluate Initialization Cells. When in doubt, I quit the kernel
> with Evaluation>Quit Kernel, particularly if evaluating code is in an
> infinite (or very long?) loop.
>
> spell and spell1 are Off by default at my machine, by the way. I'm not
> sure what that would be so here, but not at your machine. I used to have
> to turn them off manually, but that was a long time ago.
>
> Bobby
>
> On Mon, 05 Sep 2011 15:00:46 -0500, Kevin J. McCann<kjm at kevinmccann.com>
> wrote:
>
>> I have to wait for Quit to finish executing, and then execute the rest.
>>
>> On 9/5/2011 1:40 PM, DrMajorBob wrote:
>>> Put Quit in a cell by itself.
>>>
>>> Bobby
>>>
>>> On Mon, 05 Sep 2011 07:15:08 -0500, Kevin J. McCann
>>> <kjm at kevinmccann.com>  wrote:
>>>
>>>> This is a related observation to the use of Quit.
>>>>
>>>> I have an initialization cell at the top of most of my notebooks that
>>>> loads my favorite packages and sets options. If I put Quit at the top
>>>> of all that, and then execute the whole section, the Quit seems to
>>>> override everything, i.e. at the end nothing is defined.
>>>>
>>>> It appears that while Quit is executing, the other commands do, but
>>>> then the Quit kills off the results. I am not explaining it well, so
>>>> here is some abbreviated code from one of my nb's. Dump it all into an
>>>> Input cell and execute. At the end you will see that x is not defined.
>>>>
>>>> Kevin
>>>>
>>>> Quit
>>>> Off[General::spell];
>>>> Off[General::spell1];
>>>> bs = {FontFamily ->  "Arial", FontSize ->  14, FontWeight ->  Bold};
>>>> SetOptions[Plot,
>>>>         Frame ->  True,
>>>>         FrameStyle ->  AbsoluteThickness[2],
>>>>         GridLines ->  Automatic,
>>>>         PlotStyle ->  {{Red, AbsoluteThickness[3]}, {Black,
>>>>        AbsoluteThickness[3]}, {Blue,
>>>>        AbsoluteThickness[3]}, {Darker@Green, AbsoluteThickness[3]}},
>>>>     BaseStyle ->  bs
>>>>     ];
>>>> SetOptions[ListPlot,
>>>>         Frame ->  True,
>>>>         FrameStyle ->  AbsoluteThickness[2],
>>>>         GridLines ->  Automatic,
>>>>         PlotStyle ->  {Blue, AbsolutePointSize[2]},
>>>>     BaseStyle ->  bs
>>>>     ];
>>>> $Post := (If[MatrixQ[#], MatrixForm[#], #]&)
>>>> x = 22/7.;
>>>>
>>>> On 9/5/2011 7:16 AM, DrMajorBob wrote:
>>>>> No. For that, you need:
>>>>>
>>>>> Quit
>>>>>
>>>>> Bobby
>>>>>
>>>>> On Sun, 04 Sep 2011 17:06:32 -0500, Themis
>>>>> Matsoukas<tmatsoukas at me.com>
>>>>> wrote:
>>>>>
>>>>>> So, if I use ClearAll["Global`*"] at the beginning of a notebook and
>>>>>> execute all the cells, is it the same as running on a fresh kernel?
>>>>>>
>>>>>> Themis
>>>>>>
>>>>>
>>>>>
>>>
>>>
>
>




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