I am trying to set up a new tensor expression (r^hat is my unit vector):  

Can someone show me how to do it and/or point me to the right help page? 

The first part of the equation works but the rest does not. How do I get around the problem with the different indices? Another problem I have is that KroneckerDelta is no longer a tensor. Is there a way to define it as such?

Download V_Tensor.mw

I am trying to draw the Poincare section diagram related pendulum problem, article is shared below. I can not understand and code gives error, can you help me to draw Poincare section Fig. 4 of attached article?7._Energy_distribution_in_intrinsically_coupled_system [moderator: URL changed to respect IP, as per Mapleprimes Terms of Use]

pendulum.mw

Performing a search brought some results from wamp.mapleprimes.com. 

I clicked on it and firefox gave me a warning.  Is wamp.mapleprimes.com a legitamate site???

I believe I found I bug.

The 'next' statement for loop control will not work in 2D Input but it does in Code Edit Region.

From the documentation on 'next', I copied the following code into a 2D input in a document. 

Running it results in Error, invalid expression for eval; id=54 which is a missing help page.

for i to 4 do
    for j to 4 do
       print([i, j]);
         if i = j then next i;
        end if;
   end do;
end do

However 'next' without a following integer/name works fine in both 2D Input and Code Edit Region.

So is there only a subset of Maple code that will work in 2D Input?

I have calculated an expression which depends on functions. I would now like to calculate the derivative withe respect to a function  but when I try to do so I get the error “Deriving a functional ”Error, invalid input: diff received fA(r), which is not valid for its 2nd argument. There is no help page available for this error, so maybe someone knows what I am doing wrong .

I get this is because die diff function might not be able to handel a function as an argument, but how would I do it? 

Download test_funtion.mw

Hi,

Is there a way to vary C in steps of fractions of Pi ? Thanks

Q_Pi_scaling.mw

What am I missing here?  I type in a simple differential equation and I get .. unable to parse error.

For practice, I would like to calculate the left-hand limit according to the attached file. The computer does not finish. The result pi^2/6 is known from a calculation "on foot".

Download test.mwtest.mw

Hello, an interesting issue about set equivalence.

Logically, the two sets are equivalent by derivation.

The first principal case, for set A, k=0, the element values ​​are Pi/6 and 5*Pi/6, which corresponds to the case of k=0 (element value is Pi/6) and k=1 (element value is 5*Pi/6) in set B. Obviously, the k value is not one-to-one correspondence, but just a letter representing a positive integer. As for the second general case, it is the same steps I thought.

So, how to verify that the two sets are equivalent? I know Maple cannot do it in one step, but I don't know how to do it?

Download verify_set_A_and_set_B_is_equivalent.mw

I have Maple 2024 and successfully loaded the FeynmanIntegral package with:

with(Physics); with(FeynmanIntegral);

Maple confirms that FeynmanIntegral is loaded by displaying:

[Evaluate, ExpandDimension, FromAbstractRepresentation, Parametrize, Series, SumLookup, TensorBasis, TensorReduce, ToAbstractRepresentation, epsilon, varepsilon]

However, when I attempt to evaluate a Feynman integral, Maple only displays the unevaluated expression instead of computing it:

Delta(q); %FeynmanIntegral(1/p^2*1/(p + q)^2, p);

And explicitly calling Evaluate() does not compute the result:

Evaluate(Delta(q));

1. Using Evaluate() explicitly:

   FeynmanIntegral:-Evaluate(1 / (p^2 * (p + q)^2), p);

   Result: No evaluation, only displays the input.

2. Assigning the integral to a variable before evaluating:

   I := FeynmanIntegral(1 / (p^2 * (p + q)^2), p); Evaluate(I);

   Result: Still does not evaluate.

3. Using dimension= instead of d= when specifying the spacetime dimension:

   FeynmanIntegral:-Evaluate(1 / (p^2 * (p + q)^2), p, dimension = 4 - 2*epsilon);

   Result: No evaluation.

4. Checking if FeynmanIntegral functions exist:

   showstat(FeynmanIntegral);

   Result: The package seems loaded, but it does not execute calculations.

I expect FeynmanIntegral:-Evaluate(...) to automatically compute the dimensional integral using Feynman rules and return a result.

1. Is FeynmanIntegral:-Evaluate() broken in Maple 2024?
2. Are there additional setup steps needed to enable full functionality?
3. Has anyone successfully used FeynmanIntegral for automatic dimensional integration?
4. Are there alternative Maple functions/packages for computing Feynman integrals in dimensional regularization?

Any help would be greatly appreciated!

this function i have is so long and my parameter are twenty they are two much when i make a change in explore i the change is so slow and i can't see some of this parameter how act to figure when i change becuase the placement of parameters i want some of parameter being in right  and some of them being in right  and figure be in the middle for see them together can we do something like that?

figure.mw

How do we simplify the arguments of the exponential in (1)? Further how to express (1) into hyperbolic/trig functions? 
 

Download argument.mw

Hi everyone,

I'm trying to compute the cohomology group of some Lie algebras using the LieAlgebra package, but it appears that the Cohomology command doesn't provide the correct basis for the higher dimensional cohomology group, instead repeating up to the correct dimension only one element.

For example, with the following Lie algebra

L1:=_DG([["LieAlgebra", Alg1, [6]], [[[1, 3, 2], 1], [[1, 2, 3], -1], [[4, 6, 5], 1], [[4, 5, 6], -1]]])
DGSetup(L1)

the command

C := RelativeChains([])

does provide the correct k-forms on Alg1, but then

H := Cohomology(C)
provides
[[theta4,theta1],[theta1 &w theta4, theta1 &w theta4, theta1 &w theta4],[theta1 &w theta2 &w theta3,theta1 &w theta2 &w theta3,theta1 &w theta2 &w theta3,theta1 &w theta2 &w theta3], [theta1 &w theta2 &w theta3 &w theta4,theta1 &w theta2 &w theta3 &w theta4,theta1 &w theta2 &w theta3 &w theta4],[theta1 &w theta2 &w theta3 &w theta4 &w theta5 &w theta6, theta1 &w theta2 &w theta3 &w theta4 &w theta5 &w theta6], [theta1 &w theta2 &w theta3 &w theta4 &w theta5 &w theta6]

A similar thing does happen for the examples provided in the online help (e.g. example 1 from https://de.maplesoft.com/support/help/Maple/view.aspx?path=DifferentialGeometry/LieAlgebras/Cohomology). Is the command broken?

Any help is really appreciated.

when i use change maple to latex most of that equation when i want to change the place of term are change how i can fix that for example in (R) if watch in exponential the x is first term but after changing to latex are change which i have to change by hand how i can fix this issue?

Download latex.mw

For the following task I only get the numerical solution 2.356... :
sum(n=1 to oo)[arctan(2/n^2)]
The known "closed" result is 3*pi/4.