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MaplePrimes Posts are for sharing your experiences, techniques and opinions about Maple, MapleSim and related products, as well as general interests in math and computing.

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  • Comments to the answers are not counted as replies in the list of recent posts, and adding a comment to an answer doesn't move the question up. 

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    Although the source is very old (Maple 6) the topic is interesting.  Should one come across the webpage Analysis and Synthesis of digital sound samples with Maple 6 located here http://www.maplesoft.com/applications/view.aspx?SID=3940&view=html they may have a dissapointing maple browsing experience when 3 of the links they try to access are broken and not available.  

    After Poker's Black Friday (April 15), I started to think about moving to Canada, and I realized that I know very little about our northern neighbor.

    I would appreciate any suggestions about a nice place with not very expensive rent (for a handicapped accessible house), safe for living, with a (very) good Internet connection, not very far from shopping places (do you have Walmarts?) etc.

    Being close (in, say, 50 miles or less) to a casino with a poker room is desirable, but not absolutely necessary.

    Thank you,
    Alec

       The Kolmogorov-Smirnov test is a widespread, simple, and effective test to check the hypotheses of the form H[0]:=F[ksi](x)=F(x), where a function F[ksi](x) is the CDF of a population distribution, a function F(x) is a given continuous function (the Kolmogorov  test), and the hypotheses of the form  H[0]:=F[1](x)=F[2](x), where F[j](x), j=1,2, are the CDF of two population distributions, both are assumed to be continuous (the Smirnov test).  See the ...

    A Plot Component (on the right below) can act as a kind of 2-dimensional "slider" for inputing values of two parameters at once.

    The polar plot (on the left below) makes use of both values.

    If you click in the right Plot, and drag around the mouse cursor for a while, then the left Plot will be continuously updated.

    Make sure to execute the collapsed code-edit region, to initialize it. (Just click on it, to execute. Or expand, look, and right-click on it.)

     

     

     

    Click any point above, & Drag

     

    Download plotslider1.mw

     

    This is in response to a Question about the speed and memory use of an animated DEplot. The problems are that the example's animation was slow to create, and prohibitively expensive to save in a Document.

    An alternative approach is to combine multiple calls to plots:-odeplot with a call to plots:-fieldplot to supply the background flow arrows. This is a lot faster. It takes less memory to create and run, but the GUI may still consume too much resources saving it. The good news is that it's so much faster that it's not inconvenient to re-run the entire thing from scratch. And so it's quite feasible to remove all the expensive output from the Document prior to saving and thus avoid the whole resources problem.

    The original questioner also wanted to visualize with resect to two varying parameters. So I've also done an implementation of that using Embedded Components and two Sliders.

    Here is the old DEplot animation. It takes about 40 sec to create it animation on an Intel i7.

    Here is the new combined odeplot+fieldplot animation. It takes a second or two to create its animation on an Intel i7.

    Here is the DEplot in Embedded Components. It's very slow, and the image doesn't change smoothly with the sliders.

    Here is the new combined odeplot+fieldplot in Embedded Components. Its image changes pretty smoothly with the sliders.

    I encourage completely quitting the GUI (not just restart, or close Document and re-Open) between comparison runs of these implementations, of you want to get a really good feel for the effects of both running them as well as saving them (with and without all output).

    For the Embedded Component documents, the functioning code resides inside the "initialize" button. (right-click, go to Component Properties, Action When Clicked, only if you want to inspect it.) To run those two  Documents, execute all the commands (use the triple-exclam from the menubar if you like), and then press the "initialize" button, and then move the sliders.

    The difference in performance is related partly to the use of hardware datatype Arrays in the PLOT structures generated by odeplot and fieldplot. (But an `arrow` primitive would help even more!)

    And (I think) there is improvement by virtue of using dsolve/numeric/parameters in the use of `odeplot`. That saves overhead from repeated cold invocations of dsolve/numeric. And DEplot doesn't support that, since it expects as argument the system of DEs and ICs. The newer `odeplot` command accepts the procedure returned by dsolve/numeric, and thus allows for efficient repeated setting of parameter values. The `fieldplot` command doesn't need the solution of the DE system at all: it just needs the DEs.

    I would have considered wrapping the whole combined approach up into a single command, but it might have to accept separate options for the view ranges, in order to always look its best. A smart version might be able to deduce the computed ranges from the odeplot output, and then create the background fieldplot based on that.

    I've made a little progress in definig a new set of constants from the generalized continued fraction that I mentioned in my previos post.

     

    See https://oeis.org/wiki/Convergents_constant.

    Why is it possible for http://www.mapleprimes.com/users/abraham to continue posting spam ? It is incredibly irritating for me, and I presume it must be for other bona fide users. Why can't the account be disabled, made inactive, or whatever is necessary to stop this ridiculous activity ?

    In this post I will describe a little about the OU course MS325: Computer Algebra, Chaos and Simulations, which I took last year.

    MS325 is a level 3 OU applied mathematics course, which means, roughly that it is pitched at the level of a final year mathematics undergraduate. It is split into three components: Computer Algebra, which teaches the use of Maple and Maple programming; Chaos, which teaches dynamical systems, deterministic chaos and fractals, with an emphasis...

    The Magma package in Maple 15 includes the command IsSubMagma.  This tests whether a specified subset of a magma is closed under the binary operation that defines the magma.  For example, consider the following Cayley table for a group of order four.

    > with( Magma ):
    > m := << 1, 2, 3, 4 |

    Time and time again you get caught up working with Maple and before you know it your 20 minutes of alloted time has turned into almost 1 hour.

    Here's a little procedure alarm message to remind you it's time to start shutting down.  Start this procedure in a seperate worksheet and enter the number of minutes before you want your Maple alarm message popping up.  Open a new worksheet and start your work.  When the time is up, your message will pop up unless...

    > restart; with(LinearAlgebra); assume(omega, real, omega > 0);
    > G := 9;
    > z := (xi^2+xi/(1+xi^2))/(1+xi^2);
    `output redirected...`> print(); # input placeholder
    > C := `<,>`(1-z, seq(sin((n-1)*Pi*z), n = 2 .. G));
    `output redirected...`> print(); # input placeholder
    > g := Transpose(C);
    `output redirected...`> print(); # input placeholder
    > A := Multiply(C, g);
    `output redirected...`> print(); # input placeholder

    > restart; with(LinearAlgebra); assume(omega, real, omega > 0);
    > G := 9;
    > z := (xi^2+xi/(1+xi^2))/(1+xi^2);
    `output redirected...`> print(); # input placeholder
    > C := `<,>`(1-z, seq(sin((n-1)*Pi*z), n = 2 .. G));
    `output redirected...`> print(); # input placeholder
    > g := Transpose(C);
    `output redirected...`> print(); # input placeholder
    > A := Multiply(C, g);
    `output redirected...`> print(); # input placeholder

    All too often one wants a list of dates from one date to another for use in a graph or table. 

    All searches on the subject have evaded me.  I do not have Maple15 but I think the tools for such luxuries are there in the new Finance package. 

    Without Maple 15, how can I do this in a simple manner?

    ** edit ** I have converted this to a post, plus added more info below

    Well I have created a procedure with one way to achieve...

    I am a mechanical engineering graduate student and I use Maple daily for everything from school projects to homework. Unfortunately, printing anything out (to hand in) either (a) ends up looking absolutely terrible / enormous or (b) takes forever to format. I have to go through and apply all of these styles I've saved that make all of the fonts smaller and a different color (and when I do that, things look weird.... powers are impinging on their bases [e.g. the x and 3 in x^3 are fused...

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