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hello

i have some problem when iuse the digital libray with the delay components:

i have this error: delay variable not found in dependent variable list, [`Main.TransportDelay1.x`(T)]

it seems that the delay function in the modelica language is not well treated in MapleSim . At this level:

 

equation
    y = if 0 < delayTime then if delayTime <= time then x_delayed else y0 else pre(x);
    x_delayed = integer(delay(x, delayTime));
end Modelica.Electrical.Digital.Delay.TransportDelay;

 

Thank you for your help.

 

 

hi friends

i have a problem in maple with an error

  

Read'dsnumsort.map';
dsnumsort(Ns(0),[x,y,z]);
for i from 0 to 1000 do;
T:=i/25;
NsT:=Ns(T):
X[i]:=rhs(NsT[C1]); Vx[i]:=rhs(NsT[V1]);
Y[i]:=rhs(NsT[C2]); Vy[i]:=rhs(NsT[V2]);
Z[i]:=rhs(NsT[C3]); Vz[i]:=rhs(NsT[V3]);
KepVec[i]:=convert(crossprod([X[i],Y[i], Z[i]],[Vx[i],Vy[i], Vz[i]]),list);
KepAbs[i]:=norm(KepVec[i],2);
od:

pacecurve({[seq(X[i],Y[i],Z[i],i=0..1000)],[[-1/(2),0,0],[1/(2),0,0]]},labels=['x','y','z']);

but i see:

Error, invalid input: seq expects 2 arguments, but received 4

can you helpe me?

Thanks

Hi I have some problems with the inert view of the limit command.

 

I have upload the file. 

 

bug_limit.mw

 

Thank you.

Hello!
Please help solve this equation!

restart;

Dd:=4.9*10^(-10):
n:=4.5:
m:=3.5:
ny:=20:
B:=1.47*10^(-11):
H1:=70:
H2:=20:
H:=100:
b1:=40:
b2:=80:
delt_y:=H/ny:
A_max:=b1*H1+b2*H2+10*b1:
M:=1000:




b:=y->piecewise(`and`(y>=0,y<=H1),b1,`and`(y>H1,y<H1+H2),b2,`and`(y>=H1+H2,y<=H),b1):
y:=0: eq:=0:

for j from 1 to ny do
y:=(j-1)*delt_y+delt_y/2;

eq:=evalf(eq+b(y)*sign(y-y0)*abs((y-y0))^(1/n)*delt_y);
end do;


#eq=0, y0-?
sol1:=fsolve({eq=0},{y0});

Hello,
I am looking here for a tutor, that can help me doing some Maple programming.
I am a mathematic student and we use Maple programming.
I will be happy to pay a small amount of money for each exercice you help me doing,
Obviously the money will not be much, as I am just a student, I am just thinking you help me , and the money I pay you will be just as a Thank you gift, I thought about asking tutors at the college, but they are charging too much :( 
if anyone is interested, please contact me here.

(The procedures that we usually have to write are for example:
Aitken’s method, Newton-Raphson Method, Chebyshev Polynomial,...  I don't think it is hard for you.
Thank you very time for your time and your help.

Hi

I'm trying to use the command: DocumentTools[Retrieve](path,label), but i recieve the message "unable to retrieve label reference" no mather what i do. When i use the GUI: Insert - reference and get the value it works fine, but in that way I can't assign the value to a variable in the document.

here is an example:

The document i want to retrieve a value from:

restart;

a := 5;

#a gets the label (1)

 

The document i want to retrieve the value to:

restart;
with(DocumentTools);

path := FileTools:-JoinPath(["test.mw"], base = worksheetdir); = "C:\Users\Nicolai\CloudStation\Nicolai\Skole stof\Sem 7\test.mw"

 

Retrieve(path, "());
Retrieve(path, "(1)");
Retrieve(path, "a");

#None of the above works

 

Is it even possible to do such thing?

with best regards

Nicolai

with(Physics) :
t:=Intc(Dirac(k1+k2+k3)*phi(k1)*phi(k2)*phi(k3),k1,k2,k3) ;


# how to force
Fundiff(t,phi(-k));

# to find
3*Intc(Dirac(k2+k3-k)*phi(k2)*phi(k3),k2,k3) ;

 

hi friends

i have a problem in maple with an error

 restart:
 with(plots):with(linalg):
 r:=sqrt((xi-x)^2+y^2+z^2):
 sigma:=m/l:#linear mass density
 U:=Int(G*sigma/r,xi=-L/2..L/2);
 U:=normal(value(U));
 Us:=subs(G=1,m=1,L=1,z=1.5,U);
 plot3d(Us,x=-2..2,y=-2..2,axes=boxed,style=hidden,color=red,orientation=[-80,-130],numpoints=35^2,labels=['x','y','U']);

after this i see :

 Warning, unable to evaluate the function to numeric values in the region; see the plotting command's help page to ensure the calling sequence is correct.

can you help me?

Thanks for your time

Best regards

with(plots);

polarplot(1+2*sin(theta),theta=0..2*Pi);

 

it makes a graph made up of polar coordinate.

i wannna solve the question in cartesian coordinate

i wouldnt come up with ideas to solve it!!

please help me

 

for example)

y= r*sin(theta)

1+2y/r=r

y=(r^2-r)/2

...

...

y=x^n+x^n ....

x= something , something, something

 

Does Maple have a variable containing the directory (path) of current working file?

Thank  you.

I would like to use Newton's Method (the multivariate one) in order to solve a system of equations. From what I understand, fsolve is essentially MAPLE's version of the multivariate Newton's Method. Is there a way to do the multivariate Newton's method any other way, other than fsolve? Also, is there a way to specify our own initial guess and tolerance for the Newton's Method and to get other details such as the number of iterations?

of the improper integral of exp((1-x)/((1-x)^2+y^2)) over the unit disk x^2+y^2 <= 1 with Maple? For purists the function is assumed to be undefined at (1,0). It is not so difficult to verify that statement  by hand. It is not easy to prove that with Maple.

My try was

f := evalc(exp(Re(1/(1-x-I*y))));


VectorCalculus:-int(f, [x, y] = Circle(`<,>`(0, 0), 1), numeric);

and

evalf(Int(f, [y = -sqrt(-x^2+1) .. sqrt(-x^2+1), x = -1 .. 1]));
.

Edit. The formula for f.                  

PS.

 

 

 

How to find all nonisomorphic undirected graphs with 5 vertexes? Of course, with Maple.

Hello everyone,

 

I am working on a program in Maple and got stuck in exchanging limits for integrals. For example, if I have an expression of following type.

Eq:=4*Int(f(x), x=0..1/3)+Int(x*f(x), x=0..2/3);

I want to convert it in to an expression of form

4*Int(f(x),x=0..x)-4*Int(y,x=1/3..x)+ Int(x*f(x), x=0..x)- Int(x*f(x), x=2/3..x)


In short, I want to split both the integral at x but flip in limits in the second integral. I tried as follows which did not work

applyrule(Int(f::anything,y=c::numeric..d::numeric)=Int(f,y=c..x)-Int(f,y=c..x), Eq)

Please, help me!

Thank you for your time.

How do i proceed to solve two differential equations?

Two equations two unknowns is easy to solve in polynomial algebraic equations. Example: x+y=5; x-y=3; The solution is x=4; y=1 by adding the equations we arrive at.

The two equations are second order differential equations with two variables say temperature T (x,y) and velocity c(x,y). Assume any simple equation (one dimensional as well i.e. T(x) and c(x) which you can demonstrate with ease, I have not formulated the exact equations and boundary conditions yet for SI Engine simulation.

Thanks for comments, suggestions and answers expected eagerly.

Ramakrishnan

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