Hi,

I have to simulate some kinematic movements of machine. There are tree differential equations (ce2,ce2 amd ce3) which describe movement (there are angular velocity ac1, ac2, ac3 or angular beta, ang, teta ). I know exact solution in MatLab but I am trying do it the same in Maple (13). Unfortunatelly results-curves I recieved are not the same (In Matlab I have very smooth). Is there any Maple expert who can check my equations...

Hi, I have the following equation and I would like to solve the equation "EQN" for n with 0<taut<1 and 0<taum<1 but I received not only a solution but also the warning "solutions may have been lost". I wonder why.

The equation is:

> EQN:=6581019.044*n*(ln(3.*(6110.-1811.*n+1980.*n*taum+1200.*n*taut-7800.*taum-7800.*taut)/(-25423.*n+28140.*n*taum+18000.*n*taut+74230.-101400.*taum-117000.*taut))/(10000.-1000.*n)^(3/4)/taum)^(50/13)-.2407407407*ln...

If I run the below code which finds the optimal portfolio weights given a portfolio
target return G then I get a nice solution:

restart:
with(Optimization):
with(LinearAlgebra):

n := 4:
C := 10000:
G := .1*C:

X := Vector[column]([seq(x[i], i = 1 .. n)]):
ER := Vector[column]([0.5e-1, -.20, .15, .30]):
Q := Matrix([[0.8e-1, -0.5e-1, -0.5e-1, -0.5e-1], [-0.5e-1, .16, -0.2e-1, -0.2e-1], [-0.5e-1, -0.2e-1, .35, 0.6e-1], [-0.5e-1, -0.2e-1, 0.6e-1, .35]]):

Dear my friends

I have a computer with Intel Core 2 due CPU. When I am solving the Maple program by it, only 50 percent of CPU power is involved. How can I use the whole power of CPU during executing a Maple program?

I also applied "kernelopts(numcpus=2)", however it has not any positive influence.

Yours

Dear all,

I'm trying to derive the equation of motion for a mechanical system using lagrange equation

I do have u := sum(sum(U[2*i, n](t)*sin((2*I)*pi*x/a)*sin(n*pi*y/b), n = 1 .. 1), i = 1 .. 1); so u is a function of (x,y,t) but U is function of t only.

T:=subs(x = (1/2)*a, diff(u, t))^2;

Therefore T is function of (x,y,t)  and it has terms containing U(t) and d/dt(U(t))

now I need to differentiate T with respect to d/dt(U(t)) .

Dear, slamu aleekum

If i have

M=100,    j run from 1 to 15,     i run from 1 to M

How can i use       i-j mod M

                          i+j mod M

thanks for help

A prospective customer recently asked if we had a MapleSim model of a double pipe heat exchanger. Heat exchangers are a critical unit operation in the process industries, and accurate models are needed for process control studies.  I couldn't find an appropriate model so I decided to derive the dynamic equations, and implement them using MapleSim's custom component interface.  I'll outline my modeling strategy in this blog post.

I have a nonlinear partial diff eq which I am sure has been categorized.  How do I go about finding literature on the eq & the approach to solve it.  I have visited various websites that have catalogs of nonlinear partial diff eq's.  The problem is notation is so NONSTANDARD I have no IDEA what I am reading.  I have included a PDF eq_of_choice.pdf with my notation which I am familiar with. ...

Included below is vector partial diff eq I am working with.  To get rid of the time deriv's I took the LaPlace transform & the remaining spatial eq in the s-domain is listed.  To make matters simpler I set beta = 0 to get rid of the curl of the field.  What remains is essentially the Helmholtz eq.  To simplify further I just found the homogeneous soln for the x direction only.

As can be seen the eigenfunctions are exponentials with s beneath...

gam := 1.4;
p[L] := 1;
u[L] := 0;
rho[L] := 1;
p[R] := 1;
u[R] := 1;
rho[R] := 1;
p1 = 1/2*(p[L]+p[R]);
A[L] := 2/((gam+1)*rho[L]);
A[R] := 2/((gam+1)*rho[R]);
B[L] := (gam-1)*p[L]/(gam+1);
B[R] := (gam-1)*p[R]/(gam+1);
a[L] := (gam*p[L]/rho[L])^(1/2);
a[R] := (gam*p[R]/rho[R])^(1/2);
if p1 > p[L] then
     f[L] := (p1-p[L])*(A[L]/(p1+B[L]))^(1/2);
     df[L] := (A[L]/(p1+B[L...

Hello,

These days I thought a question:how to creat a variable delay?

As illustrated in Fig.1, if delay time T is constant, then the output is y(t)=u(t-T), so we can use a block named "Pade Delay" in maplesim to achieve our purpose.As shown in Fig.3.

If delay time is variable,namely,T(t), then the output is y(t...

Hi All,

I'm new here and to Maple and this is my first post.

How do I get maple to evalaute the following expression:

sum(exp(-1/2*(((psi-theta) + 2*pi*n) / (sigma))^2), n=1..infinity);

psi and theta are angles, sigma is a constant - basically psi, theta and sigma are numbers. In fact the summation is where n is a member of Z (set of integers) but I will be happy with a solution for n= 1..infinity.

Solving the system

 a1 := 2*x2-x3-x4-x5-x6-x7;
 a2 := -2*x1+2*x3-x4-x5-x6-x7;
 a3 := x1-2*x2+2*x4-x5-x6-x7;
 a4 := x1+x2-2*x3+2*x5-x6-x7;
 a5 := x1+x2+x3-2*x4+2*x6-x7;
 a6 := x1+x2+x3+x4-2*x5+2*x7;
 a7 := x1+x2+x3+x4+x5-2*x6; b := x1+x2+x3+x4+x5+x6+x7;
 solve({x1 >= 0, x2 >= 0, x3 >= 0, x4 >= 0, x5 >= 0, x6 >= 0, x7 >= 0,
 b = 1, a1 <= 0, a2 <= 0, a3 <= 0, a4 <= 0, a5 <= 0, a6 <= 0, a7 <= 0},...

Though I have been a casual Maple user since M12, I really don't know how to use it well, and am just learning it. I set myself a few tasks to help me discover its potential. I find that I learn better if I have some goal, even if it is just a sample goal.

In the accompanying file, I want to see how to use M14, and explore how to use Legendre polynomials.

Q: In (3.4), is there a cleaner way to declare the sequence?

Q: Am I using sequences correctly in this file?

I am trying to duplicate the material that is shown in the accompanying PDF file, where the plot actually comes from the calculations, much as I am trying to do with Maple 14.

Q: (3.9) gets the correct coefs, but not very pretty...is there a better way?

Q: I eventually stumbled upon (3.10), which looks correct, but when I dragged it to the plot and dropped it, I got only the first Legendre polynomial, not n of them. How do I get that?

Q: How do I show that I dropped L on the plot? The legend shows Curve 1 and 2.

Q: Is there a way to combine (3.8) and (3.9) into one stem, for example, by using array subscripts? I tried and failed.

Legendre_polynomial_.mw

Legendre_polynomial_.pdf

how can I find the average of numberrs in a list. For example, I want to find the average of [4,6,8]. Thanks!