hi guys,

suppose we have general metric form in 4-D. I want to calculate Covariant derivative of Riemann, Ricci and Weyl tensors.

please help me.

with best,

I dont know why I could not solve this problem.

I have attached my worksheet.

Please anyone help me to get solution to this problem.

Thank you so much

fypppp.mw

DLMF offers different encodings for mathematical expressions. Example:

I was wondering if TeX or pMML (never seen before)  can be imported into Maple and subsequently be used as  Maple Input.

When taking notes I sometimes use the palette to insert a matrix into a worksheet. When I do this, the main aspect that is useful to me is being able to visualize matrix expressions as I would write them.

I would like to do the same but for determinants of matrices. Is there a way to get almost the same thing as with the matrix palette, but with vertical bars denoting a determinant rather than the brackets used for matrices?

How do we compute integrals of functions or expressions that have units attached?
For example

The results of the integrals have the wrong units.

Download integration_with_units.mw

I have X=+-1,

and I want to calculate X^n.

 Thank's

Dear members of the forum, please tell me if it is possible to calculate the series presented below by Maple 2022. As far as I understand, first you need to calculate the inner and then the outer sum, but I don’t know how to do this with the help of the program, this series does not converge, as it seems to me, but I can be wrong, if the series diverges, then I need to show it.

Sorry for my ignorance, but maybe I wrong apply such commands for calculation this sums:

Sum(F, a = 1 .. infinity, b = 1 .. infinity) = DefiniteSummation(F, a = 1 .. infinity, b = 1 .. infinity)

I understand, that Sum () not be able to recive more than one args, but I don't understand how to make this calculation...

Any idea? Thanks for advices and help!

Dear All,

I have an executable program which I have generated with Fortran. Is it possible to run such a program from Maple? It sounds a bit weird but that would simplify my computation, since I would not need to use scripts in Linux. Thank you very much.

Cheers.

Let's say we have four equations and four unknowns and we use solve to find a solution.

The return value of solve is a set.

Here is an example

If we want to make the four expressions above procedures, the manual way is to basically copy the right-hand side of each expression and then write

T__1 := (R,m__1, m__2, g, I__s) -> ...

T__2 := (R,m__1, m__2, g, I__s) -> ...

a := (R,m__1, m__2, g, I__s) -> ...

alpha := (R,m__1, m__2, g, I__s) -> ...

Is there a way to do this automatically from the return value of solve?

If the return value were a list, I would use something like

T__1 := unapply(result[1], R, m__1, m__2, g, I__s)

T__2 := unapply(result[2], R, m__1, m__2, g, I__s)

a := unapply(result[3], R, m__1, m__2, g, I__s)

alpha := unapply(result[4], R, m__1, m__2, g, I__s)

But the return value is not a list.

So, in summary my quesions are

1) what, in general, is the best way to obtain the desired procedures?

2) is there a way to use the strategy I suggested if the result were a list, but for sets?

Download solveEqs.mw

i need to differentiate this equation 

Potential energy eq:
p := (m1*a1 + m2*(a123 + z(t)))*sin(theta(t))*g + m3*(sin(theta(t))*(a1234 + z(t)) + cos(theta(t))*a5)*g;

  p := (m1 a1 + m2 (a123 + z(t))) sin(theta(t)) g    + m3 (sin(theta(t)) (a1234 + z(t)) + cos(theta(t)) a5) g

i have tried these 2 methods

diff(p, theta)

diff(p, theta(t))

but both of them comes out 0 

where they should give 

diff((m1*a1 + m2*(a123 + z))*sin(theta)*g + m3*(sin(theta)*(a1234 + z) + cos(theta)*a5)*g, theta);

       (m1 a1 + m2 (a123 + z)) cos(theta) g + m3 (cos(theta) (a1234 + z) - sin(theta) a5) g

how is the syntax for partial differentiating a pre defined equation dependent on time.

I would like to know if there is a difference in the definition of the following words to describe a collection of code in Maple.  Specifically, is there a difference between an internal command, an internal procedure and an internal function?  Or are the folks who wrote Help using the three words interchangeably?  

For example, Help describes "restart" as a command.  That seems reasonable.  It also describes "evalf" as a command. 

Sin, cos and tan are described as functions.  That also appears to be reasonable.  "eval" and "convert" are also labeled as functions. 

However, "unassign" is a procedure as is "animate".  I could understand that since one might assume there is nothing returned. And yet one can assign an animation to a variable/name.

Section 1.4 of the Programming Guide discusses Maple Library Commands under the subheading of "procedures".  However, section 3.15 discusses "function types" which with section 3.8 implies these collections of code might be viewed as functions. (And then there is the function operator of a procedure.) 

I'm trying to compartmentalize the Maple language, but maybe I should not. My inclination is to call everything for which one uses a functional call (section 3.8) as a procedure.  Any assistance would be appreciated.

Dear Maple users

I have encountered a very strange error at one of my students. When using functions from the Expression Palette, she receives an error. It happens every time she is using this Palette. A reinstallation of Maple didn't help solve this issue. When using Command Completion for the very same function (for example cosine or square root), it works properly. 

She did send a Maple file to me in order for me to investigate it. I opened it and reexecuted the entire document. The error messages remained. I tried applying the functions from the Expression Palette myself resulting in the same errors. I even opened a new document and tried it again. Still an error. Then I closed Maple completely and opened it again. Within a new document, I applied a function from the Expression Palette. Now it worked!! I can't seem to understand  the logic behind this behavior. The file sent to me by the student obviously contain some kind of error, but why will this error spread to a new document, which I have opned on my own computer? My own computer does not have any issues with Maple. 

I have attached the Maple file with the errors and a screen shot. I hope someone can explain this strange behavior and tell me how I can help this student make Maple work again. 

Kind regards,

Erik V.

Maple file:

Error.mw

After saving and closing my maple file, it was corrupted when I tried to open it again later. 

I tried searching for a solution without any luck...can someone help me repair it?

Regnede_Eksamenssæt.mw

(When it asks to save it as Regnede_Eksamenssæt_1 only a small part of the document is included)

restart;
with(geometry):
with(plots):
_EnvHorizont:lName = 'x';
_EnvVerticalName = 'y';
Vdot := proc(U, V) local i; add(U[i]*V[i], i = 1 .. 2); end proc;
R := 5;
ang := [3/4*Pi, -(3*Pi)/4, -Pi/6,4*Pi/9];
seq(point(`||`(P, i), [R*cos(ang[i]), R*sin(ang[i])]), i = 1 .. 4);
pts:=[seq(P || i,i=1..4)]:
seq(dsegment(`||`(seg, i), [`||`(P, i), `||`(P, irem(i, 4) + 1)]), i = 1 .. 4);
Triangle(Tr1,[P1,P2,P4]);
EulerCircle(Elc1,Tr1,'centername'=o);
circle(cir, [point(OO, [0, 0]), R]);
dist := proc(M, N) sqrt(Vdot(M - N, M - N)); end proc;
display(draw([P1(color = black, symbol = solidcircle, symbolsize = 12), 
P2(color = black, symbol = solidcircle, symbolsize = 12), 
P3(color = black, symbol = solidcircle, symbolsize = 12), 
P4(color = black, symbol = solidcircle, symbolsize = 12),seg1,
seg2,seg3,seq4,Tr1,Elc1,
cir(color = blue)]), 
textplot([[seq( [ coordinates(`||`(P, i))[], convert(`||`(P, i), string)],i=1..4], 
,align = [above, right]), axes = none);
does not recognize neg4 or tr1? I don't know to manage. Thank you.

When we use Maple input to define a procedure in a worksheet in Document mode, how do we evaluate/execute the command. I am used to just hitting <Enter> when using 2d Math. Today, I've been trying to use Maple input, but when I hit <Enter> nothing happens, or something does happen that messes up the definition such that I get a 

Warning, premature end of input, use <Shift> + <Enter> to avoid this message.

right in the middle of the procedure which then generates a 

Error, global declaration unexpected outside procedure or module
Error, missing operator or `;`

and the only way to even execute and see these errors is by executing the whole worksheet. 

Attached is an example: 
 

I can hit enter on the 2d math version, but not on the first 1d math version. On the 1d version, if I go to right after "end:" and hit <Enter> I get an error: Error, reserved word `end` unexpected.

Download 1dmathproc.mw