## how do I simulate optimal control in maple (direct...

How do we write code for optimal problem using Pontryagin's maximum principle for simulation.

## How to fix the behaviour of the LinearAlgebra[Eige...

In Maple18.02:

Hso := Matrix(8, {(1, 4) = -x, (1, 6) = I*x, (2, 3) = x, (2, 5) = I*x, (3, 2) = x, (3, 5) = -I*z, (3, 8) = y, (4, 1) = -x, (4, 6) = I*z, (4, 7) = -y, (5, 2) = -I*x, (5, 3) = I*z, (5, 8) = -I*y, (6, 1) = -I*x, (6, 4) = -I*z, (6, 7) = -I*y, (7, 4) = -y, (7, 6) = I*y, (8, 3) = y, (8, 5) = I*y})

av, AV := LinearAlgebra[Eigenvectors](Hso)

Error, (in Polynomial:-Quadratic) type `truefalseFAIL` does not exist

This does not happen in Maple17.

## Wierd digits on my Graphs!!! ...

Friends

I have plotted some figures and saved them yesterfay!

now once i opened them some nonsence digits appear on the figure! see the picture please. anyone has similar experience? how to solve it!

Dont make me disappointed maple! two days work is invain now !

## Error, (in maplemint/expression) not implemented P...

Hello,
When I try to put the Gcdex in a procedure and start maplemint, then there occurs an error.

`Gcdex(x^2 - 1, x - 2, x ,'s','t') mod 3;`

--> works

But:

```restart; a := proc()     Gcdex(x^2 - 1, x - 2, x ,'s','t') mod 3; end proc; maplemint(a);```

Then there is an error I don't understand.

`Error, (in maplemint/expression) not implemented POLY`

By the way I have a fundamental problem to understand, where the values s and t are saved after calling Gcdex (or Quo, Rem, etc.). Till now I thought, that variables s and t are created, but when I declare s, t at the beginning as local variables and start maplemint, then there is something like:

```    These parameters have the same name as constants:       3     These local variables were used before they were assigned a value:       r::name, (-x-1)::name, (x-1)::name```

So the names of s and t changed, they don't assign a new value? I don't understand that.

## defining a vector and store data in it, then writi...

I having a hard time with defining a vector, in order to store in it some data, then plot it and export it to a file, I copied all what's in the help instructures but it doesn't work everytime, please it's urgent for my PhD thesis !

## Groebner basis and polynomial ideals...

Hi, I have a big system with 27 polynomial equations in 16 unknowns: f_1=...=f_27=0.  I can store these equations but I cannot calculate a Grobner basis of the ideal  J generated by my polynomials (allocation problem) - I use the library "with(FGb)"-  What interests me is whether my system is minimal in the following sense.

If, for example,  I remove f_1, is the ideal generated by (f_2,...f_27)  J again ? That is to say, is f_1 in the ideal generated by f_2,...,f_27 ? I would like to get an answer "yes" or "no" for each removed  f_i.

My question: can we solve the problem above  without calculating a Grobner basis of J?

## GetcompiledProc Error...

Hello every one,

I'm using Maple to create a compiled program of my model Maplesim. I had a error with "getcompiledProc" command, which is :

Error, (in GetCompiledProc) non-numeric initial condition for `Main.RAB.value`(t): Float(undefined)

the "Main.RAB.value(t)" represent a probe used to visualize an output of my system.

Does anybody had a such error ?

Larbi ANIBA

## Vectors and Euler's method help...

Hi, I need help with this little university assignment.

See the thumbnail below.

I have been away from the class because of a staph infection and missed the notes about vectors and Euler's formula.

It would be helpful if someone could give a rundown about how to solve the problems or give a general solution.

-Thanks

## pdsolve->Warning: System is inconsistent --- Can I...

Hello,

I have a PDE system. When I use pdsolve it gets me the messege " pdsolve->Warning: System is inconsistent". Is there a way I can see which equations breaks the system down?
For this system, it's difficult to see from ayeball where the problem is.
Thank you!

test.mw

## odd bug in maple...

i copy maple code from notepad to maple in maple window,

there is no error

my function in the code

explicit define parameters are Local type

for example

appendto("...");

func1(aaa)

Local aaa;

but when i run cmaple to read the code text file in window 8

it return error

missing operator, syntax error

at Local aaa;

originally

i have defined

Local aaa, ii;

for ii from 1 to nops(aaa) do

etc.

but it has error too,

then i change to one by one

Local aaa;

Local ii;

still have error at Local aaa;

## How to update legend in display sequence of plots?...

I'm displaying a series of point plots as an animation, and would like to update a displayed parameter as well.  I have a nested list L[t] where there's a set of points for each t, and for each t there's also a numerical value M that I'd like to display.  (In my real problem, L[t] is the number of particles in each of several states, and M is the rms deviation from am algebraic probability distribution.)

The closest I've gotten (for a simple L and M) is the following, but it displays all of the M values in the legend at once:

with(plots); with(Statistics);

L := [[1, 2, 3, 4, 5, 6], [2, 4, 6, 8, 10, 12]];

M := [1, 2];

display([seq(PointPlot(L[t], legend = M[t]), t = 1 .. 2)], insequence = true)

I don't need this to be in the legend.  Is there a way to display only the current value of M for each t?  Thanks very much.

## Is my way finding symmetries is correct ?...

Dear All

In following I tried to find symmetries of certain partial differential equation taken from paper "Group classification and exact solutions of generalized modified Boussinesq equation". But the determining equations are not matching with equations obtained in paper.

 >
 >
 (1)
 >
 (2)
 >
 (3)
 >
 (4)
 >
 (5)
 >
 (6)
 >
 (7)
 >
 (8)

The third equation in (8) can simplify last equation. This will give us as  is non zero.

 >

Regards

## How can I install Maple on another pc?...

Good morning, I'm a student and I installed Maple 18 on my PC, as a "Single User Profile". Unfortunately, I had to buy another computer, so now I'm trying to install the program on my new one. Even if I enter my Purchase Code and my details, Maple says that no more activations are left in my account, even if the expiration date is on March 2020. Is it possible to activate again the program?

Thank you,

Laura

## how i can pdsolve this nonlinear equations...

thanksoffcenter2.mw

 (1)

 (2)

 (3)

#####################################

 (4)

at x=

 (5)

 (6)

 (7)

############################################

at x=0

 (8)

 (9)

################################################

at t=0 for x= [0,La]

 (10)

 (11)

 (12)

 (13)

 (14)

 (15)

 (16)

######################################################

at t=0 for x= [0,La)

 (17)

 (18)

###################################################

at t=0 for x=La

 (19)

 (20)