restart;gc()

a:=Matrix(1..5,1..5,(rand(1..1000))/1000)

b:=a*1000;

b[4,4] has the value 858.000000000000114   Why isn't this value 858. so that it matches the consistancy of the rest of the matrix??

Dear All,

I have a simple question: having a Matrix A, how to make a copy of this matrix called B, which modifications do not influence the values of Matrix A.

Simple example:

hey,

i am studying maths at uni and i have a test on maple tomorrow.

one of the revision questions is: "find a partial fraction expansion for p(x)/q(X) (given p and q) and extract the numerator of the 6th summand in the partial fraction expansion.

i defined p and q, and typed "convert(p/q,parfrac,x);" but that would not give me the result!

any help? please...

Hi,

I'm taking a class in DEs and Im trying to use maple to solve some of them.

the thing is I can't find a way to solve the following in maple: y" + y = 2xsin(x) .....

can somebody help me in that???

Thanks in advance.

Karim

Here's what I am trying to do:

1. I launch a Maplet from a webpage either using a local copy of Maple or over the web via MapleNet)
2. When this Maplet iterminates I want to run a PHP (or Javascript or ...) program.

In order to do this, the web page needs to have some way to detect the termination of the Maplet. Does anyone have a way to do this?

One approach I've considered is to have a Javascript function that starts the Maplet, waits for the Maplet to terminate, then continues with it's job. But, the usual Javascript action is to start a window, after which the script continues to execute. If I could get a process ID for the window displaying the Maplet, I oculd probably have the Javascript spin its wheels until the process ID no longer exists in the list of active processes.

I can also imagine a situation where the Maplet writes a "cookie" somewhere on the client computer. Then the Javascript sits idle until it detects an appropriate trigger in the cookie. But, where to put the cookie? Is there a way to extract the directory from which Maple is run? Or, Maple's lib directory. (Within Maple I know there is the libname command. But, is there a way to send this information to a non-Maple job?

I've thought about using system (or ssystem) but the command to be executed depends on the OS of the system on which the Maplet is being executed.

I'm interested in all varieties of solutions: theoretical to complete implementations.

Thanks in advance,

Doug

Hi, I am new to maple, and I am just trying to get to grips with it but I need to know how to do the following (I have been looking through the help guide but everything I try seems to not work)

1). I need to find the coefficient of xyz² via a single function (Rather than just finding it once expanded or in a multistep process) to the equation (x+y+z)⁴

From what I have worked out its something like coeffs(expand((1)), x, y, z^2), but I am going wrong somewhere ...

let w=exp(2∏i/n) with i=√-1

find (1-w)(1-w^2).....(1-w^n-1) for n=3,4,5.

what do you think the general result might be for all n???

any help appreciated:)

Is there a way in Maple to compute a radical ideal?

For example, how to compute radical ideal of "a+b" with a,b in any field?

Thanks in advance.

Gepo

Tank you "Preben Alsholm". Your solution is very nice. But I have a question. When I use

implicitplot(eq(x), x=0..10)

for myself equation, I have a plot with 2 lines where have symmetry with respect to x-axis, but when I use your notation I only have the line under x-axis. Why?

For my physically work I need the upper line.

Hi!

I have one equation consists of "x" and "y(x)". This equation does not have any analytic solution, but I found a numeric solution by using "implisitplot". But, apparently this solution is not very good because if I want to plot anything which is related to either itself or its derivatives such as:

a(x) := y(x) + 1

or

b(x) := diff(y(x), x) + 1

I don't have any good result. What shall I do? Can you...

Hi!

Thanks a lot. you solved my first problem. Now I have a new problem. Consider I have an equation like:

w(z) = 1-(2/H(z))*diff(H(z),z)

I want to plot "w" with respect to "z", but since with latter solving I don't have any functional form for H(z) I can't. What's your suggestion for this?

Thank you!

Say I have an equation like

equation:= (r,theta) -> J(0,5*r)*sin(r)*theta

(where J is BesselJ)

and I want to integrate 'equation' over 'r=0..5' or any other limit. 

With, "Int(trial2(r, theta), r = 0 .. 5)" or even by using "int" instead of "Int", I'm not able to solve the integral. Even by using 'evalf' I get the same result back. 

If I get rid of the 'theta' term from 'equation', of course the integration ends up as a real...

I want to verify a solution satisfies a given differential equation,

deq := diff(y(x), x) = y(x)/(x*(ln(x)-ln(y(x))));

sol := x = y(x)*exp(C*y(x)+1);

Because the differential equation and the solution are complex,I tried many way,but failed.

How can I verify sol is just a general solution of deq?

Can you help me? Thanks a lot.

Dear guys!

I know that an analitical solution of an aquation of order "n" like this is impossible. But I give you a simple example. For the equation y(x)^2+y(x)+x=0, we have a solution like y(x)=(-1+-sqrt(1-4*x))/2. But here we have an equation of the form

y(x)^(-0.2)*[y(x)^2-(1+x)^3-(1+x)^4]=1. I'm sure it has a numerical solution. What do you think? 

This is what I'm trying to do:

> d := 40*Unit(m);                      

> a := .170*Unit(m/s^2);

> x := d+(1/2)*a*t^2;

> plot(x, t);

Error, (in plot) the units `m` and `m/s^2` have incompatible dimensions

Is there any way to tell Maple that my t is a variable of seconds?