## Numerically Integrating an ODE...

Hi,

I have the following ODE:

dx/dtau=s-rx+x^2/(1+x^2)

Where r,s,x vary over an interval. 0<r<0.5 ; s and x any real value (positive). Our instructor wants us to numerically integrate this. He has a program available on his website but I would like to know how to do this in maple. I have the answers to the question already but I would like to use maple to find the answers. This is for a course in Nonlinear Dynamics and Chaos. I am not very proficient...

## Implicit Function Help!...

I've seen a few posts regarding implicit functions in Maple, but I've not seen any that can help my case...

(I should point out that I am new to Maple as well).

My function is hc=[1/(2π*(√2)*a*f2)]*ln(hc/4), and f=(a0-a)/a0

I have managed to get so far- Maple has accepted the function as an equation, and I want to plot hc as a function of f, which, as you can see, varies according to a. I've tried...

## Incomplete Worksheet (Once again)...

Hello everyone

Yes, im just another one with problems during loadingproces.
Just lost my assignment in advanced engineering mathematics, and I do not know what to do.

Anyone who can help a friend in need?

The file is attached.

- Patrick

## there were problems during the loading process."...

Hi.

I would like some help with this. As so many others  i get this meassage "There were problems during the loading process. Your worksheet may be incomplete." when i treid to open my, almost done, Math assignment.

so i looked the problem op and found that i could retrive alot of my work by changing some lines of code. I could not find the problem.

Any help?

-JRR

ps. I realy realy realy hope you guys can help me!

## Sum elements from a vector...

Hiim using maple 14 and tried to apply the sum of vector's elements, y appears a error (Error, unsupported type of index, n)

a := Vector(5, {(1) = 1, (2) = 2, (3) = 3, (4) = 4, (5) = 5});
> sum(a(n), n = 1 .. 5);

Error, unsupported type of index, n

please need some help

Thanks

## Return only the base angle?...

If I have

F = x + 2π_Z1~

Is there a function/operator I can apply to F which returns only x, discarding 2π_Z1~?  That is, I want to return only the base angle, and dump the added integer multiple of 2π term.

## Where Maple is statistics compared...

Good Morning.

I would like to know where Maple is statistics compared with other software. As a justification for the thesis i am doing. I found a page http://www.scientificweb.com/ncrunch/, but a report in 2008. I wish something more recent.

Thanks

## maple 14 codes are not working...

i set up maple 14 on win 7 64 bit,  maple 14  opens but codes don't  work. how can i solve this problem?

## Maximum value of function on graph...

I am interested to know how the find the maximum value in a function of f(x,t) over an interval {x=a..b, t=c..d}. I have searched this forum and the web and can not find anything to do it.

I have plotted the function and can visually see the maximum, however, although I have tried many methods I can not calculate the maximum value.

Any assistance would be appreciated. If possible, I would also like to calculate the mean and minimum value for the function.

## Solving a non-linear system of equations...

For the following system:

x1 := M*(cos(phi)-a*cos(phi)) / (1-b*cos(2*phi))

x2 := M*(cos(phi)+a*sin(phi)) / (1+b*sin(2*phi))

y1 := M*(sin(phi)+a*sin(phi)) / (1-b*cos(2*phi))

y2 := M*(sin(phi)+a*cos(phi))/ (1+b*sin(2*phi))

I'm solving for M(x1,x2,y1,y2), eliminating a, b, and phi.

I've tried

solve({x1=X1, x2=X2, y1=Y1, y2=Y2},{M,a,b,phi},AllSolutions);

and

sol := eliminate({x1 = X1, x2 = X2, y1 = Y1, y2 = Y2}, {M, a, b, phi});

## Is this a bug in randperm?...

I have the following Maple worksheet:

restart;
randomize();

select1 := combinat[randperm]([1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);

Because of the "randomize" function, each time I execute this worksheet I should expect a different output. However, the real output is always the same every time. Is this a bug in combinat[randperm]() or am I missing something?

Attached file: randperm1.mw

## fourier coefficients...

HI,

I am trying to solve for fourier coefficients but can't figure out the error in the code. Need help to debug the code.

Also if possible how to find the harmonics in the curve defined in the code.

following is the website from where i got this code

http://www.mapleprimes.com/questions/121551-Fourier-Serie-And-Discrete-Fourier-Transform

fouriercoefficient_h.mw

## Multiplying Two Plots...

Hi everyone,

Is there any possibility to add two plots together and have the wave shape which will be combination of the two.

Equation for two plots is attached.     help.mw

## fsolve - 4 equations - 4 Unknowns...

Dear Maple Users

I am looking for specific answer, please see the following code,

by trial and error I estimated proper values for 4 parameters, and corresponding equations become close to zero.

However I need to make it automatically via maple, what can I do?

If I give ranges for parameters, there is no answer existed.

Thank you.

you can download worksheet from the below:

## multiplying two sum equations...

HI,

I am struggling with simple multiplication shown in the attached file:

Is there any specific multiplication command I should use.

Pls guide me in respect of how to make plot after multiplying A and B