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Hi Everybody,

I'm having some problems simulating an algebraic system in Maple.  I want to do this for a larger system of equation (~20 equations/20 variables, with 3 inputs), but I'd like to get an idea of the form this should be in.

So, using an example out of Maple help:



inp1:=Vector[column]([1,2,3,4,5,6,7]) * 0.1;


Error, (in DynamicSystems:-Simulate) should never be here


I don't understand what this error means.  Reading the example in the help files, says the second argument should be a vector of input values.  What I would assume this would do is plugin x = 0.1, then solve y=sin(0.1), and output y.

Am I missing some syntax, or is my inputs wrong?  There are examples of how to set up an algebraic system in the help files, but no examples of how to simulate them.


Thanks in advance for any help!






Diff(x1,t) = x2^2,
Diff(x2,t) = u,
y = x1

result in

Diff(y,t$2)-4*u^2*Diff(y,t) = 0
2*u*x2 - Diff(y,t^2) = 0
x1 - y = 0

is it possible a general and generic method to apply some steps on system below

Diff(u1, t) = u1*u2-u1*u3,
Diff(u2, t) = -u1*u2+u2*u3-(1/2)*(conjugate(u2-u3)*(u1*u2-u1*u3)+conjugate(u1)*(-u1*u2+u2*u3)-conjugate(u1)*(u1*u3-u2*u3))/conjugate(u1),
Diff(u3, t) = u1*u3-u2*u3+(1/2)*(conjugate(u2-u3)*(u1*u2-u1*u3)+conjugate(u1)*(-u1*u2+u2*u3)-conjugate(u1)*(u1*u3-u2*u3))/conjugate(u1),
y = u1


I'm searching for the third differential equation that will transform the following two equations non-autonomous system into a three equations autonomous one:




diff(z(t),t)= ...





I like to plot the Bode diagram of function transfer. For that purpose, i use Dynamicsystem package.

I obtain my transfer function by 2 different methods : 
- direct method
- state space method.

The issue is the fact that i don't obtain the same results with the 2 methods.



I am trying to make a custom on maple but when i get an error on dynamicSystems saying:

> sys := DynamicSystems[AlgEquation](eq, inputvariable = [Altura(t)], outputvariable = [Teste(t)]);
Error, (in DynamicSystems:-AlgEquation) algebraic equations cannot depend on past/future values of the input/output

But if i change AlgEquation to diffEquation i get no error. I dont have any diff equation on the system. This is happening with one of the "equations":

Hello. I am creating a custom component similar to the one that maplesoft has as an example (the discretized counterflow heat exchanger), but with some diff. The problem is that when i execute dyamic systems i get an error saying:

Error, (in DynamicSystems:-ParseSystemInputs) cannot match the arguments to an appropriate system

Is this a problem on my equation (something that i may have forget) or is another thing? Are the arguments type of dynamic system in the right "type"?


I am trying to make a simple model of a combustion. To start i am just calculating the composition of the products for a complete combustion and flame´s adiabatic temperature. The equations used to solve the model are:


nch4 = nco2;
2 * nar = 2 * nco2 + nh2o + 2 * no2;
7.52 * nar = 2 * nn2;
4 * nch4 = 2 * nh2o;
nch4 * hfch4 + nar(hfo2 + 3.76 * hfn2) = nco2(hfco2 + cpco2(Tad - 25)...

plotting using DEplot...

February 13 2012 allen 5

i have a differential equation like below


sys1 := diff(y(t), t) = (800-y(t))*y(t)/(100+y(t))-450




i tried to plot this diff equation but received an error message:

Warning, plot may be incomplete, the following error(s) were issued:

> restart:
> sys := TransferFunction(1/((1+0.1*s)(1+0.002*s+0.0001*s^2)));
> BodePlot(sys,range=10^(-1)..10^(3));

I get the following warning:
             Warning, transfer-function(s) are not rational-polynomial(s) in s

Why?.. How can I make it work without any warning?

Thanks everybody for help!


I am in need of help with Maple Linearize and an exremely crypitc and most un-helpful error message. What does this mean:

> linmod := Linearize(syss, parm, linp);
Error, invalid input: Linearize uses a 4th argument, linpoint (of type {list(`=`), set(`=`)}), which is missing

I can find nothing in the help in this.

Linearize works fine when running a sample program from the help files, but fails when I run my equations.  


I use maple to verify some examples in my textbook. The followings are two warnings which I came across.


> with(DynamicSystems); sys := TransferFunction((1+.2*s)/(1+.1*s));
> ResponsePlot(sys, Step());

When running the codes above, a warning appears unexpectly.
Warning, cannot evaluate the solution past the initial point, problem may be complex, initially singular or improperly set up

With this question, I...

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