MaplePrimes Questions

I am using Maple 2015.2 on a Windows 10 machine.  I use the plot command to generate a simple graph.  I then use the Manipulator Pan tool to change the axes limits.  The system does not redraw the function with the new range limits.  The parameters in the Axis properties have been changed appropriately but the graph does not display for the new limits.  Even if I change the parameters without using Manipulator Pan tool, the system does not redraw the function with the new range limits.  Any guidance about what I am doing wrong?  I am attaching an example file in case the behavior continues on other systems.

20160711_example_of_graph_pan_issue.mw

Thanks,

Wayne

Dear All

It is well known that the package "PDEtools" is helpful in finding infinitesimal transformations for PDEs which I illustrate as follow:


with(PDEtools):

DepVars := [u(x, y, t)]

[u(x, y, t)]

(1)

declare(u(x, y, t)):

u(x, y, t)*`will now be displayed as`*u

(2)

U := diff_table(u(x, y, t)):

PDE1 := U[t, x]+(3/2)*u(x, y, t)*U[x, x]+(3/2)*U[x]^2+(1/4)*U[x, x, x, x]+(3/4)*sigma*U[y, y] = 0:

G := [seq(xi[j](x, y, t, u), j = [x, y, t]), seq(eta[j](x, y, t, u), j = [u])]:

declare(G):

eta(x, y, t, u)*`will now be displayed as`*eta

 

xi(x, y, t, u)*`will now be displayed as`*xi

(3)

DetSys := DeterminingPDE(PDE1, G, integrabilityconditions = false):

pdsolve(DetSys)

{eta[u](x, y, t, u) = (1/9)*(-2*(diff(diff(diff(_F1(t), t), t), t))*y^2-4*(diff(diff(_F2(t), t), t))*y+6*sigma*(-(3/2)*(diff(_F1(t), t))*u+(1/2)*(diff(diff(_F1(t), t), t))*x+diff(_F3(t), t)))/sigma, xi[t](x, y, t, u) = (3/2)*_F1(t)+_C1, xi[x](x, y, t, u) = (1/6)*(-2*(diff(diff(_F1(t), t), t))*y^2-4*(diff(_F2(t), t))*y+3*sigma*((diff(_F1(t), t))*x+2*_F3(t)))/sigma, xi[y](x, y, t, u) = (diff(_F1(t), t))*y+_F2(t)}

(4)

The set (4) gives infinitesimal transformations. How we can write  vector fields corresponding to arbitrary constant C1and arbitrary functions "F1(t), F2(t), F3(t) "?"" 

``


Download Writing_Vector_fields.mw

Regards

I am having 26th degree polynomial univariate equation , I used Isolate to get the roots. but I am getting some extra roots which are not true they I even tried to substitute those roots in original equation then I got non zero answer instead of getting nearly zero answer.How is it possible??

 

equation looks like:

-12116320194738194778134937600000000*t^26+167589596741213731838990745600000000*t^24+1058345691529498270472972795904000000*t^22-4276605572538658673086219419648000000*t^20-23240154739806540070988490473472000000*t^18-5442849111209103187871341215744000000*t^16+49009931453396028716875310432256000000*t^14+74247033158233643322704589225984000000*t^12-2762178990802317464801412907008000000*t^10-25947900993773120244883450232832000000*t^8-7468990043547273070742668836864000000*t^6-567730116675454293925108383744000000*t^4+3703566799705707258760396800000000*t^2-4742330812072533924249600000000

Solutions i got:

[t = -4.162501845, t = -2.295186769, t = -1.300314688, t = -.8048430445, t = -0.6596008501e-1, t = -0.4212510777e-1, t = 0.4212510777e-1, t = 0.6596008501e-1, t = .8048430445, t = 1.300314688, t = 2.295186769, t = 4.162501845]

t=4.162501845 give me non zero answer when I substitute it in the equation given above:

I got this answer: 4.750212083*10^39

 

Some years ago a postdoc working with me insisted to use Maple, since he was used to it. He left me some *.mws files with some calculations we had published together. I'd like to re-use the code now, preferably transposed to C or another programming language (there is not much use of Computer algebra in the code). Unfortunately it appears not so easy. I found the free Maple reader, and at least can now see the code. However, I did not find a way to copy-paste code from the Maple reader to a text file, or any other way to store the code in readable format (avoiding the Maple reader). I try to store the code by printing from the Maple reader with a kind of pdf writer, and a process started which kept my Laptop busy for more than an hour now without any output.

At the moment it looks like the two years of Postdoc work is lost, thanks to Maple and its strange restriction policy.

Can somebody let me know how to save the Maple input code of a *.mws file in a text file?

 

 

Hi there,

            Recently, I encountered a problem. I have a function( omega as its variable)  (18)

 gamma*sqrt(4)*sqrt(omega^2*C2^2*R4^2/(C2^4*R4^4*beta^2*gamma^2*omega^4+C2^2*(1+gamma^2*(beta+1)^2-2*gamma)*R4^2*omega^2+1))

I tried to find a point where its first derivative equals 0. In this case, Maple returned four solutions. In my

question, both beta, gamma, R4 and C2 >0, I want it to return a real positive solution, the first term

in (19) (i.e. 1/(sqrt(beta *gamma) *1/R4 C2).

 

I know it is easy to find out the positive real roots in this case. This question seems to make no sense.

However, sometime I came across an expression complicated enough that I cannot tell whether it is real

positive.

Is there a approach to find a real positive solution of an symbolic eqution?

Thanks in advance!

 

                                                                     A University student in BeiHang University, Beijing

I'm trying to call a C function which returns an array. The example on the help page http://www.maplesoft.com/support/help/maple/view.aspx?path=examples/ExternalCalling is to pass in an array with known dimensions, which will be updated in the C function, but I wonder if this is the only way to do it. For example if I have an array of unknown dimensions beforehand, what is the best approach to return this array?

Thanks!

I am trying to solve a matrix system to find the relative arrival rates of a queueing network using Gauss-Seidel.The maple commands are below:

restart;
with(Student[NumericalAnalysis]); with(LinearAlgebra);

A := Matrix([[1, -.333, -.333, -.333], [0, 1, -.333, -.333], [0, -.333, 1, -.333], [0, -.333, -.333, 1]]);

IsDefinite(A, 'query' = 'positive_semidefinite');

true

b := Vector([1, 1, 1, 1]);


IterativeApproximate(A, initialapprox = Vector([1, 1, 1, 1]), tolerance = 10^(-3), maxiterations = 20, stoppingcriterion = relative(infinity), method = gaussseidel);


Error, (in Student:-NumericalAnalysis:-IterativeApproximate) check that the augmented matrix has the correct dimensions

I do not understand this error as the matrix is 4x4 as shown. Can anyone see where I went wrong?

 

I am currently working on an adaptive question in Maple TA 2016 and it seems that there is a bug in the drop - down list functionality: 

After I click "Verify" in a section, the answer disappears even though I choose it to be displayed. The window simply goes back to showing (Click for List) instead of keeping the answer, see the screenshot below.

 

Perhaps I am doing something wrong, though I have used Lists extensively in the previous version and never had that problem ..

 

Thanks for your  help!

Elisabeth

 

 


 Hello every one,how do i integrate from this expression?

``

restart

ode := (1+B*T(x))*(diff(T(x), x, x))-M^2*T(x)^(n+1)+B*(diff(T(x), x))^2;

(1+B*T(x))*(diff(diff(T(x), x), x))-M^2*T(x)^(n+1)+B*(diff(T(x), x))^2

(1)

``

 

Download integral.mw

 

 

Hello,

I have a number of outputs, and I want to put them into an Array witrhout specifying the index of the array, is there a way I can put all of them at once without putting them one by one? I am currently using Append, is there any other way other than Append?

I have Maple 2016 loaded on a MacBook Pro running the El Capitan operating system. What is the keyboard button sequence for typing a Greek letter?

Thanks

Tom

I have been in touch with Maplesoft trying to get this version for windows (they are not able to create a download for this). I have codes that used to run in Maple 6 but not in Maple 7 or later. (Maple V should work as well).

If you any of have this version, please let me know if I can try it out for a limited time (I have always had licenses from Maple V Release 3 or 4).

I am not able to post those codes for obvious confidentiality reasons.

 

Thanks

 

(I tried my code in Maple 7, but no use). 

Assume i got an equation like f(x):=2*x-tan(x); how to us solve or other function to give me that this equation got 2 root: x=1/2*(tan(x)) and x=arctan(2x).

^^ hope everyone can help.

Thank for spend time reading.

When using seq function below in the second call, it does not generate a sequence of functions with 'a' being 1, 2, and 3, and I had expected. 

First seq function call is just to show that it works without the function "x ->" wrapping.

I could of couse use unapply as in the third call, but I had expected the second call to work.

Am I doing anything wrong, or is this a Maple bug?

Trying to understand how Maple works, I wanted to read the documentation.

For the "plot" statements, there is a "view" option, and I found the build in documentation in version 2016 to say:

So based on this a list should be given with two range elements, and not other valid option format was described.

However, based on examples I fould, it appeas that a single range element (giving the Y range I guess) is also valid, like in:

Where am I missign the elaborate documentation that describes the legal option type?  Or is Maple programming just some kind of guess and try hacker language ? ;-)

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