If i want to do mathematical modelling for planetary motion, how can maple help me with it?

 I want to plot phase portrait but i get some errors. I didn't understand errors? Can anyone help me? zuhal_faz_portresi.mw

Dear power users, I probably have 2 dummy questions, which I show in the attached worksheet. 

1. it looks to me that the equation can be further simplified than done by maple

2. is there a quick way in cleaning up the array by replacing the strings by something as NaN (not a number) so that I can use the array for numeric calculations?

Thank you for helping me out     Download Questions.mw

Download Questions.mw

As we know, since the order about the element Perm([[1, 2], [3, 4, 5]]) of S₅ is 6. Then  the C₆ is a subgroup of S₅, but why IsSubgroup(CyclicGroup(6), SymmetricGroup(5)) return false? Is it a bug?

Of course, we know the A₅ of 60 order is an unsolvable group, but as the wiki here, There are also some solvable groups in the same 60 order. Similarly, although map(IsSolubleNumber, [60, 120, 168, 180]) will give false, there are some solvable groups in orders 60, 120, order 168, and order 180. But how to find these corresponding solvable polynomials by maple? I tried to generate them using random polynomials like this:

with(GroupTheory);
do
    do poly := randpoly(x, degree = rand(6 .. 8)()); until irreduc(poly);
    G := GaloisGroup(poly, x);
until IsSoluble(G) and is(GroupOrder(G) in {60, 120, 168, 180});
poly;
galois(poly, x);

But I didn't get any result even after one night..

Hi folks

If you try this simple integral 

simplify(int(P(q)*(Dirac(k-q)+ Heaviside(k-q)),q = 0..infinity)) assuming k>0; 

it returns int(P(q), q = 0 .. k), completely ignoring the delta function. However, if you expand the integral first:

simplify(value(IntegrationTools[Expand](Int(P(q)*(Dirac(k-q)+ Heaviside(k-q)),q = 0..infinity)))) assuming k>0;

 it gives the correct answer 

P(k) + int(P(q), q = 0 .. k)

Looks like a bug to me?

Cheers!

I've been asking a similar question：

How does Maple call external programs such as nauty?

Recently I used Mathematica to call these gadgets very succinctly, so I revisit the topic, and maybe Maple can do it as well, but I just didn't do it the right way.

• nauty and Traces are programs for computing automorphism groups of graphs and digraphs. There is a small suite of programs called gtools included in the package. For example, geng can generate non-isomorphic graphs very quickly. 
• plantri and fullgen are programs for generation of certain types of planar graph.

We note that binary executables of above two programs for Windows are not officially available. Fortunately, I recently compiled them by cygwin.  Of course, other operating systems can make it easier to use them. See attached two compressed files of compiled nauty and plantri programs for Windows.

The official websites of the two programs are listed below.

• https://pallini.di.uniroma1.it/
• https://users.cecs.anu.edu.au/~bdm/plantri/

So, I found that Mathematica works very well for running these programs by Import. We list the following two examples: first example is to get all non-isomorphic 10-order 2-partite connected graph, and the second example is to get all 14-order non-isomorphic  quadrilateral graphs (the planar graphs in which any face is 4-face).

glist10 = Import["!D:/nauty27r3/geng -c -b 10", "Graph6"]; // AbsoluteTiming
Length[glist10]

g14 = Import["!D:/plantri52/plantri 14 -q -g ", "Graph6"] // AbsoluteTiming

I tried maple's Import or ImportGraph functions, but both failed.

restart: 
with(GraphTheory):
L:=ImportGraph("!D:/nauty27r3/geng -c -b 10 -g",output=list):
L2:=Import("!D:/nauty27r3/geng -c -b 10 -g"):

Error, invalid input: GraphTheory:-ImportGraph uses a 2nd argument, format (of type {string, symbol}), which is missing
Error, (in Import) must specify format for this input

The problem seems to be not recognizing compilations symbols " !".  I don't know if Maple can do this like mathematica.

Dear all

I need to  `Put markers to emphasize the point of intersection between f, and g

iteration.mw

thank you

Given a polynomial, e.g. 3*x^2 + a*x*y + b*y^2, is there some built-in function which can give me a list of monomials, with each monomial represented as [coefficient, [exponent_of_x, exponent_of_y]] ? The above polynomial would turn into something like [ [3, [2,0]], [a, [1,1]], [b, [0,2]] ].

It's not difficult to write this procedure from scratch. The procedure would require two arguments: (1) the polynomial itself, (2) which symbols are considered variables (in the above case, x and y). The remaining variables, a and b, would then be treated as constants that appear as coefficients. But I'm wondering if there's a built-in function I can just use.

Hi everyone, Could you help me to get a general solution to the following ode? Here rho and z are constants.

Thanks.

Download ode_rlmt.mw

Does maple software support Benders decomposition technique for Mixed Integer Linear Programming? If no, how we can implement it in maple? Any suggestions. 

Thank you

x := [0, 1, 2, 3, 4, 0, 1, 2, 3, 4, 0, 1, 2, 3, 4, 0, 1, 2, 3, 4, 0, 1, 2, 3, 4]

y := [0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4]
z := [0, 0, 0, 0, 0, 0, .689376362, 1.378752724, 2.068129087, 2.757505449, 0, 1.02920355, 2.0584071, 3.087610649, 4.116814199, 0, 1.216469264, 2.432938529, 3.649407793, 4.865877057, 0, 1.325720912, 2.651441823, 3.977162735, 5.302883646]

How to plot the contour plot for the given data

i want that maple show the value on countor plot like this

with(plots)

contourplot(x*y/486, x = -h/2 .. h/2, y = -a/2 .. a/2, filledregions = true)

Dear Users! Hope everyone is fine here. I have some points x_0,x_1,..,x_N and corresponding to these number have values y_0, _1, ..., y_N as,

restart
a := 1; b := 5; h := 1; f := 1/x; N := (b-a)/h;
for i from 0 while i <= N do x[i] := h*i+a; y[i] := eval(f, x = x[i]) end do;

Now I want to develope the following difference table using the values of y_0, y_1, ..., y_N as,

where difference column generated using the following concept

Please help me in this regard. Thanks in advance

I have been studying the solutions of the equation below using Maple and Mathematica. 

Here, I want to express the solutions for k. In Maple, the solution is imaginary. As one may see below.

On the other hand, if one solves that  exact equation with Mathematica, then one has real solutions. That is,

Based on the above, I have a few questions:

1. What is the correct solution for the first equation above? That is, are the solutions real or complex?

2. How may I obtain the real solutions, k_{1,2}, above using Maple?

Attached below you may find my mwfile with my doubts.

Mydoubts.mw

Thanks in advance.