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...

Dear everyone,

  Hello,

  I have a question related to copy and paste in Maple 16.

 Consider an input like

**********************************

eq1:=4*x^n*y^m+3*x^2+5*y^2;

f1:=map(t -> `if`(match(t = c*y^d, y, 's'), subs(s,c), NULL),
      convert(eq1, list));


f2:=map(t -> `if`(match(t = c*y^d, y, 's'), subs(s,d), NULL),
      convert(eq1, list));

Sir/Madam

My Version of MAPLE is 13.02

I have the following expression on my worksheet:

(63/8) ((cos(Θ))^5)[G,H,L,P,T,U]^5 -(35/4)((cos(Θ))^3)[G,H,L,P,T,U]^3 + (15/8)(cos(Θ))[G,H,L,P,T,U]

I do not need the factors of [G,H,L,P,T,U] and I want to delete them, but all my efforts in the past few hours are in vain. I have tried to highlight those expressions and then use the EDIT -> DELETE ELEMENT...

Hi,

Is there a way to generate Java or C code to implement a general nth order linear ordinary differential equation?

I am looking to be able to send the coefficients and have it compute the time waveform given initial conditions.

Regards.