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Writing a function to get a Random planar graph...

Asked by: vs140580 495
graphtheory connected
July 17 2022
1  3

Any way to write a function to get a RandomPlanar connected graph

That I have function say RandomPlanar(n,m) where n is the number of vertices and m is optional parameter and is the number of edges 

Font-size of caption, labels and axes on plots sma...

Asked by: OD 5
font pdf export
July 17 2022
1  3

Maple 2021.
I expect after exporting to pdf view of page with plot like on fig. 1.

It means with font=[TIMES, ROMAN, 12] as in maine text.
But I obtaned this view of page on pdf (fig. 2) with smaller font-size.

In previouse versions there are no the problem like this.
Dear community, how to fix this annoying inconvenience?

 fig. 1.  fig. 2.

Efficient and accurate way to find intersection po...

Asked by: Stretto 260
July 17 2022
1  2

I have a closed curve(parameterized by t) with self intersection and I'd like to locate the x-y coordinates of the intersection. fslolve only returns 1 intersection. I've tried to use a finite step method but it is way to slow even with rough stepping and becomes very inaccurate. Does maple have anything built in to handle this?

Help writing code...

Asked by: mohammad1 15
homework pde differential-equations
July 17 2022
2  2
 

  

Download 111.mwFractional_محلوله.pdf

Hello my friends
How can I write the results inside the Maple code as in the picture? That is, writing the results in terms of gamma and alpha

Get a numpy matrix output of python as a input to ...

Asked by: vs140580 495
python import exceltools
July 16 2022
0  0

A python program will output several  adjacency matricies which is to be given as a input to a maplesoft code by writing it to some some kind of  file or so with a sample.

The python file will generate several adjacency matrices need to send it as a input to my maple code

With a small sample codes with interface please.

The help will be surely acknowledged

How do I solve time fractional thin film equation ...

Asked by: delvin 60
pde differential-equations fractional-derivative
July 16 2022
1  5

I want to write a program for the time fractional thin film equation to be converted into an ordinary differential equation.

With respect

Big problems with parabolic groups in the "LieAlge...

Asked by: Jaqr 90
July 15 2022
0  1

Hi,

I use Maple version 2022.1 on macOS 10.14.6.

I have big problems with the parabolic groups in the "LieAlgebra" package.

First of all in the help for "Query > Parabolic", the link refers to the help page for the commands "CylinderU, CylinderV, CylinderD" which have nothing to do with it. Also, the command "Query(Alg, "Parabolic")" does not work.

Below is a list of commands that give an error for "Query".

restart:with(LinearAlgebra):with(DifferentialGeometry):with(LieAlgebras):

L:=[
Matrix(5, 5, [[0, 0, 1, 1, 1], [0, 0, 0, 0, 0], [-1, 0, 0, 0, 0], [-1, 0, 0, 0, 0], [-1, 0, 0, 0, 0]]), 
Matrix(5, 5, [[0, 1, 0, 1, 1], [-1, 0, 0, 0, 0], [0, 0, 0, 0, 0], [-1, 0, 0, 0, 0], [-1, 0, 0, 0, 0]]), 
Matrix(5, 5, [[0, 1, 1, 0, 1], [-1, 0, 0, 0, 0], [-1, 0, 0, 0, 0], [0, 0, 0, 0, 0], [-1, 0, 0, 0, 0]]), 
Matrix(5, 5, [[0, 1, 1, 1, 0], [-1, 0, 0, 0, 0], [-1, 0, 0, 0, 0], [-1, 0, 0, 0, 0], [0, 0, 0, 0, 0]]), 
Matrix(5, 5, [[0, 0, 0, 0, 0], [0, 0, 0, 1, 1], [0, 0, 0, 0, 0], [0, -1, 0, 0, 0], [0, -1, 0, 0, 0]]), 
Matrix(5, 5, [[0, 0, 0, 0, 0], [0, 0, 1, 0, 1], [0, -1, 0, 0, 0], [0, 0, 0, 0, 0], [0, -1, 0, 0, 0]]), 
Matrix(5, 5, [[0, 0, 0, 0, 0], [0, 0, 1, 1, 0], [0, -1, 0, 0, 0], [0, -1, 0, 0, 0], [0, 0, 0, 0, 0]]), 
Matrix(5, 5, [[0, 0, 0, 0, 0], [0, 0, -1, 0, 0], [0, 1, 0, 0, 1], [0, 0, 0, 0, 0], [0, 0, -1, 0, 0]]), 
Matrix(5, 5, [[0, 0, 0, 0, 0], [0, 0, -1, 0, 0], [0, 1, 0, 1, 0], [0, 0, -1, 0, 0], [0, 0, 0, 0, 0]]), 
Matrix(5, 5, [[0, 0, 0, 0, 0], [0, 0, 0, -1, 0], [0, 0, 0, -1, 0], [0, 1, 1, 0, 0], [0, 0, 0, 0, 0]]), 
Matrix(5, 5, [[0, 0, 0, 0, 0], [0, 0, 0, 0, 0], [0, 0, 0, 1, 1], [0, 0, -1, 0, 0], [0, 0, -1, 0, 0]]), 
Matrix(5, 5, [[0, 0, 0, 0, 0], [0, 0, 0, 0, 0], [0, 0, 0, -1, 0], [0, 0, 1, 0, 1], [0, 0, 0, -1, 0]]), 
Matrix(5, 5, [[0, 0, 0, 0, 0], [0, 0, 0, 0, 0], [0, 0, 0, 0, -1], [0, 0, 0, 0, -1], [0, 0, 1, 1, 0]]), 
Matrix(5, 5, [[0, 0, 0, 0, 0], [0, 0, 0, -1, 0], [0, 0, 0, 0, 0], [0, 1, 0, 0, 1], [0, 0, 0, -1, 0]]), 
Matrix(5, 5, [[0, 0, 0, 0, 0], [0, 0, 0, 0, -1], [0, 0, 0, 0, 0], [0, 0, 0, 0, -1], [0, 1, 0, 1, 0]]), 
Matrix(5, 5, [[0, 0, 0, 0, 0], [0, 0, 0, 0, -1], [0, 0, 0, 0, -1], [0, 0, 0, 0, 0], [0, 1, 1, 0, 0]]), 
Matrix(5, 5, [[0, 0, 0, 0, 0], [0, 0, -1/2*sqrt(2), -1/2*sqrt(2), -1/2*sqrt(2)], [0, 1/2*sqrt(2), 0, 0, 0], [0, 1/2*sqrt(2), 0, 0, 0], [0, 1/2*sqrt(2), 0, 0, 0]]), 
Matrix(5, 5, [[0, 0, 0, 0, 0], [0, 0, 1/2*sqrt(6), 1/6*sqrt(6), 1/6*sqrt(6)], [0, -1/2*sqrt(6), 0, -1/3*sqrt(6), -1/3*sqrt(6)], [0, -1/6*sqrt(6), 1/3*sqrt(6), 0, 0], [0, -1/6*sqrt(6), 1/3*sqrt(6), 0, 0]]), 
Matrix(5, 5, [[0, 0, 0, 0, 0], [0, 0, 0, 2/3*sqrt(3), 1/6*sqrt(3)], [0, 0, 0, 2/3*sqrt(3), 1/6*sqrt(3)], [0, -2/3*sqrt(3), -2/3*sqrt(3), 0, -1/2*sqrt(3)], [0, -1/6*sqrt(3), -1/6*sqrt(3), 1/2*sqrt(3), 0]]), Matrix(5, 5, [[0, 0, 0, 0, 0], [0, 0, 0, 0, 1/2*sqrt(5)], [0, 0, 0, 0, 1/2*sqrt(5)], [0, 0, 0, 0, 1/2*sqrt(5)], [0, -1/2*sqrt(5), -1/2*sqrt(5), -1/2*sqrt(5), 0]])];

LieP:=LieAlgebraData(L,Alg):
DGsetup(LieP);
Query(Alg,"Parabolic");

 

Bifurcation of SEIR...

Asked by: ijuptilk 100
differential-equations bifurcation incomplete-question
July 13 2022
0  2

Hi,

Please can someone help me with a sample code for bifurcation? You can use parameter values for the parameters. I'm using maple 18. Below is my model:

> 

restart:
> 

f__1 := Delta -(psi + mu)*S(t);

Delta-(psi+mu)*S(t)

 (1)
> 

f__2 := psi*S(t) -(delta + mu)*E(t);

psi*S(t)-(delta+mu)*E(t)

 (2)
> 

f__3 := Delta*E(t) -(gamma+gamma__1 + mu)*X(t);

Delta*E(t)-(gamma+gamma__1+mu)*X(t)

 (3)
> 

f__4 := gamma__1*X(t)-(eta + xi + mu)*H(t);

gamma__1*X(t)-(eta+xi+mu)*H(t)

 (4)
> 

f__5 := xi*H(t) - mu*R(t);

xi*H(t)-mu*R(t)

 (5)
> 

f__6 := gamma*X(t)-eta*H(t) - d*D(t);

gamma*X(t)-eta*H(t)-d*D(t)

 (6)
> 

f__7 := b*D(t) - b*B(t);

b*D(t)-b*B(t)

 (7)
> 

f__8 := phi__p + sigma*X(t)+eta__1*H(t) +d__1*D(t)+ b__1*B(t) - alpha*P(t);

phi__p+sigma*X(t)+eta__1*H(t)+d__1*D(t)+b__1*B(t)-alpha*P(t)

 (8)

 

NULL

Download Bifurcation.mw

How can i see maple calculations?...

Asked by: VilmaR 5
integration step-by-step duplicate-question
July 13 2022
1  0

How can i see analytical maple calculations?

Define. ...

Asked by: Christian Wolinski 1650
define forall
July 12 2022
0  0

When was ?define, forall stripped from Maple?
Define used to accept all of these: Group, Linear, forall, antisymmetric, associative, binary, commutative, identity, inverse, symmetric, type, unary, zero. Was this function moved to another package?

With(Phyiscs[Vectors]) can I create vectors in mul...

Asked by: nmacsai 260
coordinates vector physics
July 11 2022
1  0

Unit_vectors_from_different_coordinate_systems.mw
 

restart

NULLNULL

with(Physics)``

with(Vectors)

NULL

It's common in mathematical physics to use cartesian unit vectors to describe the position of a point in space.

 

r_(t) = x(t)*_i+y(t)*_j

r_(t) = x(t)*_i+y(t)*_j

 (1)

Sometimes it neccessary to convert a position vector like `#mover(mi("r"),mo("→"))`(t) to another cartensian coordinate system with different unit vectors, I call the primed system. In the primed system the position vector looks like:

"(r')(t)=x'(t) (i')+y'(t) (j')"

When using Physics[Vectors] and the unit vector hat notations to define vectors in cartesian space, can I define more than one cartesian space such as:

`#mover(mi("r"),mo("→"))`(t) = x(t)*`#mover(mi("i"),mo("∧"))`+y(t)*`#mover(mi("j"),mo("∧"))`

NULL

and

  "(r')(t)=x'(t) (i')+y'(t) (j')"?

Another way to ask the same thing: Can I define the position vector in different coordinates, each system having a distinct pair of orthogonal unit vectors?

 

The short answer I think is no. Given the current implementation it's not clear how one would go about defining the relationships between unit vectors from different coordinate systems. See below.

 

In 2D the transformation corresponds to a rotation of a vector the plane. The tranformation is characterized by the rotation angle α.

 

 

 

The unit vectors from different systems are related through scalar products.

 

"(i)*i' =(|i|)*|i'|*cos(alpha)=cos(alpha)"``NULL

NULL

"(j)*(j)' =(|j|)*|(j)'|*cos(alpha)=cos(alpha)"NULLNULL

``

"(j)*(i)' =(|j|)*|(i)'|*cos(3 alpha)=cos(3 alpha)"``NULL

 

Is there a way to implement scalar products of vectors from different coordinate systems using the Physics Tensors package? Here I create three different coordinate systems. I don't know whether the unit vectors systems X and Y have the same (i, j, k) unit vectors or does each system have its own triplet?

NULL

Setup(coordinates = cartesian, metric = Euclidean, dimension = 3, spacetimeindices = lowercaselatin, geometricdifferentiation = true)

[coordinatesystems = {X}, dimension = 3, geometricdifferentiation = true, metric = {(1, 1) = 1, (2, 2) = 1, (3, 3) = 1}, spacetimeindices = lowercaselatin]
````

 (2)

Coordinates(Y, Z, Z = cylindrical)

{X, Y, Z}

 (3)

NULL

NULL


 

Download Unit_vectors_from_different_coordinate_systems.mw

 

Why does importing a MATLAB struct into MapleSim u...

Asked by: AjayMenon 60
July 08 2022
2  2

Hi there!

I have developed a component in Modelica to import values from a Matlab struct into MapleSim and use it with other components. This data is saved in a ".mat" file and the struct was constructed as follows:

% Matlab command window
% Struct name is "bemData" saved in a v7 format to be read in by Modelica
>> bemData.m33 = 100;
>> bemData.Ainf33 = 100;
>> bemData.Khs33 = 20000;
>> bemData.ss_rad33.A = [1 1;0 1];
>> bemData.ss_rad33.B = [1;0];
>> bemData.ss_rad33.C = [1 1];
>> bemData.ss_rad33.D = 0;
>> save -v7 bemData.mat

And the Modelica code I am using to try import this into MapleSim is as follows:

Modelica.SIunits.Mass M = scalar(Modelica.Utilities.Streams.readRealMatrix("bemData.mat","bemData.m33",1,1));

Modelica.SIunits.Mass Ainf = scalar(Modelica.Utilities.Streams.readRealMatrix("bemData.mat","bemData.Ainf33",1,1));

Modelica.SIunits.TranslationalSpringConstant C = scalar(Modelica.Utilities.Streams.readRealMatrix("bemData.mat","bemData.Khs33",1,1));
    
Real A[2,2] = Modelica.Utilities.Streams.readRealMatrix("bemData.mat","bemData.ss_rad33.A",2,2);

Real B[1,2] = transpose(Modelica.Utilities.Streams.readRealMatrix("bemData.mat","bemData.ss_rad33.B",2,1));

Real C[1,2] = Modelica.Utilities.Streams.readRealMatrix("bemData.mat","bemData.ss_rad33.C",1,2);

Real D = scalar(Modelica.Utilities.Streams.readRealMatrix("bemData.mat","bemData.ss_rad33.D",1,1));

I then use these imported variables to solve ODEs, and the result is incorrect. I have narrowed it down to the fact that MapleSim/Modelica imports a value of 0 in place of the original data in the struct. Moreover, there is no way to attach a probe to any of the imported variables in MapleSim (I need to force all model variables to be displayed in the Simulation results tab).

I would appreciate help in pointing out where I might be making a mistake. My primary concern is why a value of 0 is being imported in place of the actual Matlab struct data. When I use Matlab's command window to check the contents of the struct, they appear to be in order.

Also, I have saved the struct file in the same folder in which my custom component is stored (the Modelica file where I have written the code to import the data). Should I be saving this file elsewhere?

Thank you!

PDETools:-pdsolve other solutions...

Asked by: Chorux 60
pde pdsolve differential-equations
July 08 2022
1  1

Given a set (list) of PDE, is there a way to search all possible solution sets? For instance, pdsolve will output the solution

{_eta[0](t, x) = 0, _xi[t](t, x, u) = _C1, _xi[x](t, x, u) = _C2, eta[1](t, x) = 0}

for the list of PDEs below. But I am aware that there is another solution different from the above, is there way to seek these other solutions?

 

[alpha*u^2*(diff(eta[1](t, x), t))+alpha*u*(diff(_eta[0](t, x), t))-u*(diff(eta[1](t, x), t))-u*(diff(eta[1](t, x), x))+u*(diff(eta[1](t, x), x, x, t))-(diff(_eta[0](t, x), x))-(diff(_eta[0](t, x), t))+diff(_eta[0](t, x), x, x, t), -(diff(_xi[x](t, x, u), u, u, u)), -(diff(_xi[t](t, x, u), x))-(diff(_xi[t](t, x, u), t)), -(diff(_xi[t](t, x, u), x, x)), -2*(diff(_xi[t](t, x, u), x, x))-(diff(_xi[x](t, x, u), x, x))+2*(diff(eta[1](t, x), x)), diff(eta[1](t, x), t)-2*(diff(_xi[x](t, x, u), x, x)), -(diff(_xi[x](t, x, u), t))*alpha*u-(diff(_xi[x](t, x, u), x, x, x))-(diff(_xi[t](t, x, u), x))+2*(diff(eta[1](t, x), x, t)), -(diff(_xi[x](t, x, u), x)), -(diff(_xi[t](t, x, u), t))*alpha*u+(diff(_xi[t](t, x, u), x))*alpha*u+(diff(_xi[x](t, x, u), x))*alpha*u+(diff(_xi[x](t, x, u), t))*alpha*u+eta[1](t, x)*alpha*u+alpha*_eta[0](t, x)+diff(_xi[t](t, x, u), t)-(diff(_xi[t](t, x, u), x, x, x))-(diff(_xi[x](t, x, u), x))-(diff(_xi[x](t, x, u), t))+diff(eta[1](t, x), x, x), -2*(diff(_xi[x](t, x, u), u)), -2*(diff(_xi[t](t, x, u), x, u)), -2*(diff(_xi[t](t, x, u), u))-(diff(_xi[x](t, x, u), u)), -(diff(_xi[t](t, x, u), u)), -(diff(_xi[t](t, x, u), u)), -5*(diff(_xi[x](t, x, u), u, u)), -(diff(_xi[t](t, x, u), u, u)), -3*(diff(_xi[t](t, x, u), x, u)), -2*(diff(_xi[x](t, x, u), u)), -(diff(_xi[t](t, x, u), u)), -(diff(_xi[t](t, x, u), u)), -2*(diff(_xi[t](t, x, u), u, u))-(diff(_xi[x](t, x, u), u, u)), -(diff(_xi[t](t, x, u), u, u, u)), -3*(diff(_xi[t](t, x, u), u, u)), -3*(diff(_xi[t](t, x, u), x, u, u)), (diff(_xi[t](t, x, u), u))*alpha*u-(diff(_xi[x](t, x, u), u))-3*(diff(_xi[t](t, x, u), x, x, u)), -2*(diff(_xi[x](t, x, u), x, u))-4*(diff(_xi[t](t, x, u), x, u)), -(diff(_xi[t](t, x, u), u))*alpha*u+(diff(_xi[x](t, x, u), u))*alpha*u+diff(_xi[t](t, x, u), u)-(diff(_xi[x](t, x, u), u)), -3*(diff(_xi[x](t, x, u), x, x, u))-(diff(_xi[t](t, x, u), u)), -7*(diff(_xi[x](t, x, u), x, u)), -3*(diff(_xi[x](t, x, u), x, u, u))]

Maple Bombs While Entering Text...

Asked by: cbarring 20
July 06 2022
2  1

Hi.  I am using the linux version of Maple.  I seem to experience more bombs in Maple/Linux vs MathCad/Windows.  The program just froze as I was entering text.  Just text.  It is not a disaster since I make very frequent saves.  But it is very annoying.  I was a heavy user of MathCad from about 2005 to 2019.  In the early days, it bombed a lot.  But I do not recall that it ever bombed when I was entering text.  Any suggestions?  Would there be a limition on the number of text characters?  Is it Linux?  Other than this problem, it is a great program.

Searching the help system: Why are there no hits f...

Asked by: C_R 3432
July 06 2022
0  0

The Examples section on the help page of a command is important for learning, but cannot cover all uses. This is especially true for general purpose commands like "solve" or "simplify". Searching all help pages that contain the word "solve" results in too many irrelevant hits that do not contain examples.

Why does adding a bracket to a command not filter for help pages with examples using the command?

Inside a help page Find/Replace finds such strings.

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