Dear All,

I wanted to check the calcultations carried out in a Journal Article I was reading as I was not very convinced.

The objective is to find q1i, q2i, q3i in terms of px, py, and pz and constant parameters φ, a, b, h, and r.

I have realised that the results given by the article do not match with the solution to the dsolve command.

Could you please spot where the mistake is?

My Solution: IK_equations.mw

restart; with(PDEtools);
U := diff_table(Psi(`ψ_2`, `ψ_1`));
pde := `ψ_2`*(diff(Psi(`ψ_2`, `ψ_1`), `ψ_1`))+`ψ_1`*U[`ψ_1`]+2*U[] = 0;
ψ_2 Psi(ψ_2 + 1, ψ_1)

   + ψ_1 Psi(ψ_2 + 1, ψ_1) + 2 Psi(ψ_2, ψ_1) = 

  0
pdsolve(pde);
Error, (in pdsolve/info) first argument is not a differential equation

How can i solve it?

how do i solve a system of PDE's with variable coeffiecients in Maple?

Hi everyone

I have a problem with differentiating an equation. I have the following code:

(sum((x(i)-M)^3, i = 1 .. n))/(n*((sum((x(i)-M)^2, i = 1 .. n))/(n-1))^(3/2));

The values of x(i) is available in Excel and I want to import that. For this case, I copy the column and paste in maple and it seems work fine. But, I want to calculate the differentiate of the summation with respect to x(i) and M and find the answer. I don't know how to write the code appropriately.

In other words, how could I differetiate the following function with respect to x(i) and put the values from excel into it.

(sum((x(i)-M)^3, i = 1 .. n))/(n*((sum((x(i)-M)^2, i = 1 .. n))/(n-1))^(3/2));

Thank you so much for your kind attentions  in advance

I'm trying to create the set of monomials in n variables (given as a list var), up to a given degree d. Her eis my code. Any comments to make it better?

mondeg:=proc(var::list,d)
local n, mon, moni, i, j, m1, m;

   n:=nops(var);
   mon:={1};
   moni:={1};
   for i to d do
        for m1 in moni do
             #print(m1);
             moni:=moni minus {m1};
             #print(moni);
             for j to n do
                #print(var[j]);
                 m:=m1*var[j];
                 moni:=moni union {m};
                #print("moni=",moni);
             od;
        od;
        mon:=mon union moni;
        #print(mon);
   od;

mon;
end:

Much of this topic is developed using traditional techniques. Maple modernizes and optimizes solutions by displaying the necessary operators and simple commands to solve large problems. Using the conditions of equilibrium for both moment and force we find the forces and moments of reactions for any type of structure. In spanish.

Equlibrium.mw

https://www.youtube.com/watch?v=7zC8pGC4F2c

Lenin Araujo Castillo

Ambassador of Maple

Hello. I have a question on plotting discrete time plot. When I try to plot the equation below I get an error. Can't figure out where is the problem. If for example I choose for vector A () there is no error. I would appreciate your help.

Error, invalid input: DynamicSystems:-DiscretePlot expects its 2nd argument, v2, to be of type {realcons, list(extended_numeric), ('Vector')(extended_numeric)}, but received Vector(4, {(1) = 1+sin(1), (2) = 1+sin(2), (3) = 1+sin(3), (4) = 1+sin(4)})

Regards,

Tadej

Hello everyone,

I am trying to solve a differential equation using dsolve command for laplace transform.

In Equation 2, a is a constant and x(t), b(t), u(t) are functions.

What is the "_U1" in the output (4)? Is it because I have defined x(t), b(t), u(t) as functions?

Thank you in advance!

Good book to start studying maple for engineering.

Download Australopithecus_updated.mw

http://www.gatewaycoalition.org/includes/display_project.aspx?ID=279&maincatid=105&subcatid=1019&thirdcatid=0

Lenin Araujo Castillo

Ambassador of Maple

Hello,

I am so happy that this is my first time to ask a quension here.

Like the graph pasted down, i can get a graph of a ode with the odeplot in time domain.

Furthermore, i just want to get a envelope plot based on the time domain graph, just like showed in

the example graph here,

i have no way to plot it in maple,

Does anyone know a method to plot it in maple? 

Hello everyone,

Is it possible to define a short hand notation for sine and cosine functions and make the output expressed in terms of the defined notation?

For example the matrix below uses c1 instead of cos(theta1) and s2 instead of sin(theta2).

The reason I want to do this is that I am dealing with really long matrices and I need some sort of way to minimize the expressions.

Thank you!

Canberk

I am new to maple. how do i segregate different term in long PDE in maple

The development of the calculation of moments using force vectors is clearly observed by taking a point and also a line. Different exercises are solved with the help of Maple syntax. We can also visualize the vector behavior in the different configurations of the position vector. Applications designed exclusively for engineering students. In Spanish.

Moment_of_a_force_using_vectors_updated.mw

Lenin Araujo Castillo

Ambassador of Maple

I've compiled a program with Maple 18. unfortunately it gives me the message "Large sortie de plus de 1000000 noeuds". If any one have any idea to resolve this problem. Thanks you very mutch for your support. 

I tried to solve 4 simultaneous equations but the result is an empty matrix.

Is that because there is no solution or did I make something wrong?

You can download the file by using the link below.

SimEquations.mw