i have a system with 5 dif equations and five unknows. i have told to maple to solve it numerically with interactively solve comand (right cilck button). the window open like it normally does and i put values to my parameters, with an initial condition for the system (Q(0)=0). then i press numerically solve and that's all, the program just keep evaluating with no answer. i wait for 15 min, which i think is too much time, and got any answer yet.

hope you can help with this

thanks.. 
 

Download propuesta_transfer.mw

Hello

I have a procedure that builds an ideal from a specific set of polynomials and then calls the Groebner basis package to eliminate some of the variables.  Even though the procedure is running on a machine with 2 processors, 24 cores and 72 GB of ram, only one core has been used (and is always on a 100% usage).  Would the Grid Computing Toolbox be of some hope in this case?  If so,  how to insert the Grid commands so that Maple sends the calculations to the other cores (I find the document rather confusing)?   If I am talking non sense,  please let me know.

Many thanks

Ed

Hi guys,

I would like to compute the complex roots of the following equations

u*(BesselJ(0,u)^2 + BesselJ(1,u)^2) = 2 BesselJ(0,u)*BesselJ(1,u)

The function fsolve in Maple gives only 0. I was wondering whether other complex solutions could be obtained as well.

Your help is highly appreciated.

Thanks

Federiko

with(DifferentialGeometry):with(JetCalculus):
DGsetup([x],[u],E,5);
vars≔x,u,u[1],u[1,1],u[1,1,1];
PDEtools[declare](Q(vars));
TotalDiff(Q(vars),x);
TotalDiff(u[1,1],x);

Hi everyone,

Recently I came across the total differentiation command in the PDEtools. For its

documentation, I used the following link

http://www.maplesoft.com/support/help/Maple/view.aspx?path=DifferentialGeometry/JetCalculus/TotalDiff

Unfortunately, when I try to replicate this it did not work as expected. I am getting the total derivative of the expression to be zero. I do not understand where I am going wrong.

You can find my code above. I am also attaching the screen shot of my maple file.

I would really appreciate if someone could help me out. Thanks for your help.

is there a possibility to display the partial derivative of f(x,y) wrt. y as

and second order / cross-partials accordingly?

thx

jo

I have created several animated 3-d figures using Maple.  Exporting an animation as a gif file I find that with, for example, Quicktime, I can run the animation. However I cannot rotate the 3-d figures using Quicktime.  Is there some other way to make such animations available to people not having Maple, so they can rotate the figure as well as run the animation? I would appreciate any ideas about this.

The following program hangs on the last command and a hard restart is required. The computation of a 2 x 2 matrix times a 2-vector is not that hard. Any ideas as to what is happening?

Another question: if v is a vector that depends on x and y say why does
>solve(v=0,{x,y})
not work?

It should only take a few lines of code to change v=0 to the system {components of v = 0}

I have been using Maple for many years and have created many Maple procedures for my own use in different projects. My usual practice is to place the procedures in a .txt file using WordPad or NotePad on my Windows machines. Then to load, for example, a file named C:\Users\Ed\Desktop\Top Quandles\Procedures.txt I use the command 

read("C:\\Users\\Ed\\Desktop\\Top Quandles\\Procedures.txt");
or
read("C:/Users/Ed/Desktop/Top Quandles/Procedures.txt");

Or I can leave the path off if the file is in the same folder as my worksheet.

This has always worked well for me. But have two questions:

1. Is there is a better way to save and load a bunch of procedures? Also I might mention that I frequently have to go into the file and change procedures or add new procedures, data, etc...

2. Recently I had occasion to send a worksheet and a txt file to a Mac user. We were not able to get the worksheet I sent him to read the .txt file on his Mac. Any suggestions on how to do that on a Mac? We tried putting them both in the same folder and just using a simple read("Procedures.txt"); command but the Mac didn't like that.

Any suggestions about either of these two issues would be appreciated.

Thanks,

Edwin

Does anyone know if there is a simple way to write a falling factorial (pochhammer symbol) in Maple. It seems pochhammer is the rising factorial with no option to change to falling.

Thanks in advance.

I assigned

before an algebraic calculation so I would like to get  or have the program print the 70 digits of the answer and not just 10 digits. Because when I press ENTER, I get only 10 digits.

fieldplot is a wonderful tool for plotting vector fields. The option 'fieldstrength' is very useful to scale the arrows so that one can better visualize the field. I often use fieldstrength=log.

However, if one includes the RealDomain library, the fieldstrength=log option fails. I don't see why it should. Can someone enlighten me before I report this as a bug.

Hi all, 
I was only wondering if there is a way how to trunk a solution using a maple command.

I want to use it to give a truncation error which is equal to :(14/45)(D^5)(y)(0) h^5

The result I am getting is as followed: (it is correct, I just want to cut off the bit with the power of 6)
........
......
>error:=expand(Yx[i+1]-Yx[i-3]-(4*h/3)*(2*f[i-2]-f[i-1]+2*f[i]));
                          
          error :=  (14/45)(D^5)(y)(0) h^5  + 7/10 (D^6)(y)(0) h^6
                  
thank you in advance

Hi, 

I'm being unable to plot the solution to the equation

schro := {-(diff(psi(x), x, x))+(2*a*b*x^4+a^2*x^6+(b^2-a*(2*p+3))*x^2-(2*p+1)*b)*psi(x) = 0};

for the special cases of a=b=1 and p=0 and p=1

I've used dsolve and am getting Heun functions :-(

The claim is that the solutions come out to be exponentials of the form:

psi(x)=(x^p)*exp(-(a*(x^4))/4 - (b*(x^2))/2)

thanks in advance

I am trying to implement Subresultant p.r.s. algorithm for calculating greatest common divisor. The algorithm decribed in the book:

My code return the correct GCD, however the sub-resultant terms are different from the result of the built-in function. The last term a[i-1] is huge and involves fractions. I think my implementation is same as the algorithm described in the textbook.

I have attached the file. Could anybody spot anything wrong in the code? Why do fractions still appear? In my code, "lsr" is last subresultant term returned from the built-in function, the second one is my result.

Download subresultant.mw

I am having difficulty to solve the following ODE

ode:=diff(R(x),x$6)=Dirac(x-y);

with initial and boundary conditions

bcs := ((D@@3)(R))(1) = 0, R(0)-((D@@5)(R))(0) = 0, ((D@@2)(R))(0)-((D@@3)(R))(0) = 0, ((D@@5)(R))(1) = 0, (D(R))(0)+((D@@4)(R))(0) = 0, ((D@@4)(R))(1) = 0;

I want to solve the above ODE for two cases 1) x>y and 2) x<=y

Thanks