Hi, i wrote my script file some time ago, and found that I wrote `:=` in one of the equations. when I remove the ``, just let it be :=, it does not work and is spending a long time to evaluate. May I know what does `:=` means please?

Thanks.

Hi everyone, 

In my research project, I needed to evaluate a multi-variable integration. I'm trying to do this in Maple, and seems no matter I use Int or int, it failed to evaluate the integration. 

Here's my code:

I'm integrating a joint probability density function which is basically a multiplication of four PDFs of four Gaussian distributions:

> mu := 0:                                                    ...

I have problems with the time delay the procedure for computing the Hough transform of the image that Annex. Delay 5534.875 seconds. How to improve, optimize the procedure, to be more efficient at runtime?

Hough.mw 

Hi,

I have a system consisting of a multi-body system and various modelica/maple custom components. The problem is whenever I re-run the simulation even though all the simulation settings are same, the simulation results are inconsistent. There should be no difference between each simulation as all the parameters/settings are same. I am attaching two pictures which are both obtained from two successive simulations

Hello everybody! I have a question that how to show the number of roots of Eqs automatically. Followings are part of my program: 

>U:=solve({-2/phi^3*u[0]^2*diff(phi,x)-4/phi^3*w[0]*diff(phi,x)-2*u[0]/phi^3*diff(phi,x)^2, -6/phi^4*u[0]*diff(phi,x)*v[0]+12*v[0]/phi^4*diff(phi,x)^2, -2/phi^3*v[0]*diff(phi,x)+2/phi^3*w[0]*diff(phi,y)},{u[0],v[0],w[0]});

I can obtain three items roots. My question is how can I obtain the number of roots automatically by using the program!

Hello!

I have a strange issue:   I have a procedure with signum, square roots, I and float numbers. First I optimize it and then compile.  (or just run compile with option optimize=true).  As a result I get a error:

Error, (in TargetLanguageTools:-GetExprType) Analysis is not a command in the _EnvCGEngine package

Trying to understand, what is happening, I manually copy-paste the optimised procedure to the argument of compile. Then it works!!!

I have a compiled function and want to integrate it numerically.  The integration procedure first tries to evaluate the integrand with symbolic values and return a error, since the compiled function accepts only real values.  So I have to write a STUPID workaround  for manual typechecking:

integrand2 := proc (kF1, kF2, m, k, omega, q) if type(kF1, numeric) and type(q, numeric) and type(kF2, numeric) and type(omega, numeric) and type(m, numeric) and type(k, numeric...

Hello,

How can I use assign(...) inside in proc in order to affect the local variables and not the globals.

Thanks

Consider the following:

with(Physics);

Setup(noncommutativeprefix = z);

(z1*z2)*z1;

gives z1 z2 z1 as it should but

z1*z2*z1*z1;

gives z1^3 z2. Thus noncommutativity has not been respected?

What can I do?

I have an indefinite sum, for instance:

> E := Sum(f@g@@k, k=0..n);

If I use D(E), I just get: D(Sum(f@g@@k),k = 0 .. n)

> D(f@g@@k) gives the expected result: D(f)@g@@k * D(g@@k)

Doing this works:

> F := Sum(D(op(E)[1]), op(E)[2]);

   F := Sum(D(f)@g@@k * D(g@@k), k=0..n)

However I want to apply it to complex expressions containing Sums and Products. And I can't check if E is of type indefinite sum. The hasfun(E, Sum...

Let's say we have the response of a discrete system  to a unit step, the measured data is available as a vector in Maple. As example: seq(evalf[2](exp(-n/5)*sin(n)),n=0..20);

How can I find the coefficients of the transfer function G(z)=(a1*z+a2)/(b1*z^2+b2*z+b3)?

Here is a paper that describes on page 27ff how to do this with regression.
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.136.373&rep=rep1&type=pdf

Maybe there is a better way.

> with(CurveFitting); data := [[2, 10], [3, 1], [5, 4], [7, 5]];
               [[2, 10], [3, 1], [5, 4], [7, 5]]
> PolynomialInterpolation(data, y);
                    3  3       2   199     143
      ...

I have a 4 by 4 matrix that I need to augment to a 7 by 7 matrix.

I find I can use the "|" operator to append a column to my original matrix. So I can do this three times and I have a 4 by 7 matrix.

Now, the only way I have found to add the three rows I still need to add is to transpose, use "|" three times and to transpose back. While this indeed works it is rather clumsy and probably not efficient.

Is there a better way to do that better; i.e. is there...

Hi,

I need to fit a complex function to some data points Couuld you please show me what Maple operations to use?

The function is:

pn := unapply(KT*bn*(sum((dWn[i](lambda)*(sum(c[i+r]*binomial(i+r, i)*(Lmbd0(lambda)/bn)^r, r = 0 .. nterm-i))+IWn[i](lambda)*(2*lambda^3-2)*(sum(r*c[i+r]*binomial(i+r, i)*(Lmbd0(lambda)/bn)^(r-1), r = 1 .. nterm-i))/(bn*(3*lambda^2)))/bn^i, i = 0 .. nterm)), lambda);

- 'IWn' and 'dWn' are known (and long) functions of lambda.

Hello,

I'm having problems to do somehting that I guess maple should be able to do. I am solving numerically a 2nd order equation. Then Dsolve gives me the function and its first derivative.

Is there not a way to plot 2nd and 3rd derivatives??
Of course I have thought of getting f'' as a funtion of f' and f through the differential equation, but in my case that involves a complicated analytical development, and I precisely want to verify that I didnt do...