Re: Quit versus Clear["Global`*"]
- To: mathgroup at smc.vnet.net
- Subject: [mg121304] Re: Quit versus Clear["Global`*"]
- From: DrMajorBob <btreat1 at austin.rr.com>
- Date: Thu, 8 Sep 2011 05:27:04 -0400 (EDT)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
- References: <201109042206.SAA21533@smc.vnet.net> <j42b3a$rrv$1@smc.vnet.net>
- Reply-to: drmajorbob at yahoo.com
I don't think anything is happening in parallel; it takes TWO or more kernels for that. Bobby On Wed, 07 Sep 2011 07:29:35 -0500, Kevin J. McCann <Kevin.McCann at umbc.edu> wrote: > But then shouldn't the kernel restart on the next line? If not, then > when would the kernel restart? Never? After we wait a few seconds? > > Quit (* the kernel quits *) > x=1; (* shouldn't the kernel restart here? *) > > Actually, it appears that Quit takes some time to execute, and in > parallel, further commands execute, but then their results are killed > off. > > Kevin > > On 9/7/2011 5:41 AM, DrMajorBob wrote: >> No, the point is that when Quit is the first command, the kernel >> quits... >> rather than continuing to evaluate initialization cells. That appears >> entirely sequential, to me. >> >> Bobby >> >> On Tue, 06 Sep 2011 05:13:30 -0500, Kevin J. McCann<kjm at kevinmccann.com> >> wrote: >> >>> I guess the point here is that when commands are listed sequentially, >>> at >>> least with Quit at the top, they are not carried out that way, but >>> perhaps in some parallel fashion. This is not documented anywhere, and >>> I >>> don't think it is expected behavior. Further, I think it is not >>> desirable. >>> >>> Kevin >>> >>> On 9/5/2011 4:23 PM, 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 >>>>>>>>> >>>>>>>> >>>>>>>> >>>>>> >>>>>> >>>> >>>> >> >> > -- DrMajorBob at yahoo.com
- References:
- Re: Quit versus Clear["Global`*"]
- From: Themis Matsoukas <tmatsoukas@me.com>
- Re: Quit versus Clear["Global`*"]