Hi all,

There is issue with saving big numbers to txt file on WIndows

Please look at the file:

txt_issue.mw

Function save just cutting a big number.

Thank you.

Hi, Maple seems to automatically sort my list in some numerical order. Is there a way to overcome this? I want my list as it is.

Hello, 

I'm trying to calculate the convolution of the radiation forve in the time domain. I need to do a state space representation of a function K(t), where :

t=[0; 1; 2; 3];

k=[0.1; 0.2; 0.3; 0.4];

If you could help me with finding the appropriate command that give the matrix A, B C and D

just a remarque that in matlab used imp2ss (based on the Hankel SVD method)

thanks

Hello there, 

Is there any way to make the equation 'Given_eq_3_37a' in the calculation below to be 'desired'?

Perhaps, the issue of the 'L__1' and '1/L__1' might have been in the way, but perhaps that might be overcome in a different way. 

Thank you, 

In Kwon Park 

Download Q20201001.mw

Hi

I am trying to construct a controler for a UR5e robot, I have a simulation of the robot in maplesim and have started to look for a way to use multibody analysis to provide me with the Jacobian. However it only provieds the constraint Jacobian and as I have no position constraints on the robot, it returns nothing.

I then came across 

Link: https://www.youtube.com/watch?v=d3xJge_09E0&t=374s

However it is old and does not exactly say how to do it.

So I thought I should ask this wonderful comunity if they have an recomended way to construct the Jacobian from a maplesimmodel? I am still a beginner at maplesim and maple so any help is appreciated.

With thanks for helping me

Eric Ragnarsson

Hello everyone. I want to know how I can extract terms from a multivariate polynomial with the following 2 conditions:

1. It should have the lowest sum of the degree of x and of y; and
2. deg(x) - deg(y) should be either 0 or -1.

For instance, if I've f(x) = 100x^2y^2 + 35yx + 45x, I want an output of 35yx (not 45x; even though degree sum is 1, less than 2).

On the other hand, if I've g(x) = 13x^2y^2 + xy^2 + 2yx^2, I want an output of xy^2 (not yx^2 also).

Hello everyone, I have some weird problems with the maple. The problems are different for the document mode and the worksheet mode, however I strongly believe that they are connected. Starting with the document mode:

I simply cannot execute any command with the symbolic notation. As you can see below, I can execute basic mathematical calculations but I can't do any symbolic math. 


On the other hand, I can execute all the commands in the worksheet mode. For example check the screenshot. 
However, when I try to save that file in the worksheet mode, I get this error:

And, when I close the file and re-open again, I find all the stuff I wrote in the "math mode" disappeared 

In the worksheet below, variable x can be returned to type name after being assigned a value , but concatenated variable name A||1 cannot. Is there a way to return a concatenated variable to type name after it has been assigned a value, so it can be re-used as an unknown in solve commands?

Concatenate_Question.mw

Hello Everyone,

I have an equation system which is under-determined and thus yields infinite solutions. 
These usually come in the form of "_t1[1]" or similar variables. Mostly one, sometimes even two.
I am also working on a script for automated solving of a buckling problem and the solution yields of course these t-variables.
Everytime the code run, I get a different t-variable, which makes automation harder.

Please see attached code. (Of course simplified, not my actual code.)

It starts with a random matrix and a solution vector for the equation system.
The system is solved and its coefficients transfered to an equation.
However every time I hit "Enter" on the LinearSolve command, the name of the _t4[1] variable changes.

Is there a way to keep getting the same variable name? How do you work with this?

Best Regards,
Lennart

Download MultipleTCoefficients.mw

when i solve adomian polynomials there is a derivative withrespect to t and then put t is equal to zero. now i have to find the dervative of function with respect to t but it is already equals to zero. and i change the variable the Df could not b solved.
 

Download Adomian_Polynomials.mw

I want to create a simple symbolic transfer function from 2 vectors, lets say:        num=<a,b,c>

                                                                                                                               den=<c,b,a,d>
So my transfer function should look like this:
              H(s) = (a*s^2 + b*s + c)/(c*s^3 + b*s^2 +a*s+d)

This should be very simple but I haven't found a solution on the forums yet...

Thank you.

Is it possible to develop a code for base excitation problem where excitation data is of earthquake acceleration?

p.s. There are 12000 data available in EQ file.

Hi, I have a 1D wave equation with a piecewise initial value, I am trying to plot the solution with animation, I use the below code, However, it does not give me the animation I want but give me some error, which I am not understande.

My code is following:

pde := diff(u(x, t), t $ 2) - diff(u(x, t), x $ 2) = 0

h := piecewise(-1 <= x and x <= 0, x + 2, 0 <= x and x <= 1, 2 - x, 0)

ic := u(x, 0) = h, D[2](u)(x, 0) = 0

sol := pdsolve([pde, ic])

plots[animate](plot, [sol, x = -10 .. 10], t = 0 .. 5)

and the result is showing as picture below

There is a bug in simplify, specifically in `simplify/inert`, that prevents returning the simplified result if any of "inertfunctionnames" doesn't have a corresponding simplification procedure "inertsimplifications" (these are the names from `simplify/inert` code).
To see this, consider a simple example:

`simplify/%F`:=proc(X)
subsindets(X,'specfunc'(%F),2*`op`)
end proc:
Then we have:
A:=%F(a+b)+%G(a);
                   

simplify(A);
                       

Now, let's define a "dummy" simplification function for %G, e.g.:
`simplify/%G`:=proc(X) X end proc:

Only now do we get what we should:
forget(simplify);
simplify(A);
                     

The reason for this misbehavior seems to be simple: in `simplify/inert` any performed simplification is neglected if  "inertfunctions"<>{}. This should be corrected.

Dear Community,

Maple has the fancy VoronoiDiagram command, which generates Voronoi grids from a set of 2D distributed points. Does somebody know how the cornerpoint coordinates of the individual Voronoi cells  of the obtained Voronoi grid can be exported as a list of (x_i, y_i)  coordinate pairs? Could you possibly give a simple example?

Tx in advance, best regards

Andras