Is there a way to convert this FDTD code into Maple

Hy(1 to M)=0;

Ex(1 to M+1)=0;

For t=1 to T,

Ex(1)=exp(-t);

For k=1 to M,

Hy(k)=Hy(k)-(Ex(k+1)-Ex(k));

end

For k=2 to M,

Ex(k)=Ex(k)-(Hy(k)-Hy(k-1));

end

end

Thanks in advance.

Hello, 

I want to solve and plot a multitime recurrence of the Samuelson Hicks Model (http://www.mathem.pub.ro/proc/bsgp-22/K22-gh-A84.pdf).

Feel free to share any tips that could help.

Thank you. 

hello every one

i need to solve this equation

> A1 := Matrix([[a11, a12, a13], [a12, a22, a23], [a13, a23, a33]]);
> A2 := Matrix([[A], [B], [C]]);
> A3 := Matrix([[15], [0], [0]]);
> eq := multiply(A1, A2)=A3;

> solve(eq, {A, B, C});

thank you :)

Hi, I'm tying to solve the ODE by variational iteration method, programme is running, but maple answer does'nt  match to origional answer, plz tell me the mistake?

ICs y(0)=y'(0)=y''(0)=1

VIM_2.mw

Hello everyone, 

In Maple8, I tried to plot this logistic map and an error occured (Error, (in Bifurcation) `plots` does not evaluate to a module).

What is wrong into this code?

Thank you

restart: with(plots):Warning, the name changecoords has been redefined

> Bifurcation := proc(initialpoint,xexpr,ra,rb,acc)
> local p1,hr,A,L1,i,j,phi:
> global r,L2:
> hr := unapply(xexpr,x);
> A := Vector(600):
> L1 := Vector(acc*500):
> for j from 1 to acc+1 do
> r := (ra + (j-1)*(rb-ra)/acc):
> A[1] := hr(initialpoint):
> for i from 2 to 500 do
> A[i] := evalf(hr(A[i-1])):
> end do:
> for i from 1 to 400 do
> L1[i+400*(j-1)] := [r,A[i+100]]:
> end do:
> end do:
> L2 := {seq(L1[i], i = 1..acc*400)}:
> p1 := plots:-pointplot(L2, 'symbol' = solidcircle, 'symbolsize' = 8, 'color' = blue):
> unassign('r'):
> return(p1):
> end proc:
> P1:= Bifurcation(1/2,r*x*(1-x),2.5,4,250):
>
Error, (in Bifurcation) `plots` does not evaluate to a module

Hello everyone!

Do you have any idea to solve and plot a 2-time logistic map:

x(t+ 1_\alpha)= r*x(t)*(1-x(t))  ,t=(t^1,t^2)  ?

Thank you

I want to reduce all solution of the equation sin(x)^2=1/4

restart:
sol:=solve(sin(x)^2=1/4, x, AllSolutions);

and

restart:
k:=combine((sin(x))^2);
sol:=solve(k=1/4, x, AllSolutions = true, explicit);
simplify(sol);

How can I reduce solution sol := -1/3*Pi*_B3+1/6*Pi+Pi*_Z3 ?

How can I get x= pi/6+k*pi and x= -pi/6+k*pi?

In Maple 11 we have:

> A := <a,b,c>:
> a := 1:  b := 2: c := 3:
> convert(A, list);
                                   [1, 2, 3]

In Maple 2015 we have:

> A := <a,b,c>:
> a := 1:  b := 2: c := 3:
> convert(A, list);
                                   [a, b, c]

Is that change really intended?

There are no examples for ModuleDeconstruct either on its help page or in the Programming Guide. Of course, I can figure out its basic and primarily intended purpose: to render the module/object in a one-dimensional plaintext printed form, which would be useful for debugging. But I am most interested in this use described in the second sentence of this, the second paragraph of Description at ?ModuleDeconstruct [italics added]:

When the value returned by ModuleDeconstruct is printed, the output could be capable of being parsed to the original module. When used with an object, ModuleDeconstruct can return an unevaluated call to a constructor to achieve this.

That seems very powerful. Is there any example of it being used in Maple library code? in user code? Can anyone here come up with a practical use for this? A Google search turns up nothing.

Hi all,

restart;#part1
epsilon:=5:Delta1:=2:Delta2:=-4: N1:=1000:
dsys :={diff(x(t),t)=-I*Delta1*x(t)+y(t)+epsilon, diff(y(t),t)=-I*Delta2*y(t)+x(t)*z(t), diff(z(t),t)=-2*(conjugate(x(t))*y(t)+conjugate(y(t))*x(t))};

res:=dsolve(dsys union {x(0)=2*I,y(0)=0,z(0)=1},numeric,output=listprocedure);

P1:=plots:-odeplot(res,[[t,Im(y(t))],[t,Re(x(t))]],0..2):

/ d
{ --- x(t) = -2 I x(t) + y(t) + 5,
\ dt

d
--- y(t) = 4 I y(t) + x(t) z(t),
dt

d ____ ____ \
--- z(t) = -2 x(t) y(t) - 2 y(t) x(t) }
dt /
tit:=sprintf("D1=%g,D2=%g",Delta1,Delta2);
"D1=2,D2=-4"
plots[odeplot](res,[[t,Im(y(t))]],0..200,axes=boxed,titlefont=[SYMBOL,14],font=[1,1,18],color=black,linestyle=1,tickmarks=[3, 4],font=[1,1,14],thickness=2,titlefont=[SYMBOL,12]);
Warning, cannot evaluate the solution further right of 90.013890, maxfun limit exceeded (see ?dsolve,maxfun for details)

when I increase the time give this msn:

Warning, cannot evaluate the solution further right of 90.013890, maxfun limit exceeded (see ?dsolve,maxfun for details)

Hello,

Today I've playied a bit with CellDecomposition from the RootFinding package and for one of the systems with which I've playied I got an error which seems to me to be a bug related.

In particular, 

with(RootFinding[Parametric]):

m := CellDecomposition([x^3-y^2 = 0, x^2+y^2-1 < 0], [x, y])

Error, (in RootFinding:-Parametric:-CellDecomposition) Segmentation Violation occurred in external routine

Did I make a mistake somewhere or Maple 2015.1 faild?

I am working on a problem involving sums in Maple and I find Maple's facilities lacking.

Specifically; I want to convert the square of a sum into a sum of squares plus the cross terms (which is a subtask of a larger problem). So I start with

sum(E[n],n=1..N)^2;

and immediately get stuck as I do not find any command that does anything with it. The expansion of this is known and easy to derive:

sum(E[n],n=1..N)^2 = sum(E[n]^2,n=1..N) + 2*sum(sum(E[m]*E[n],m=1..n-1),n=1..N);

Maple knows nothing about this relation. I have checked out packages like SumTools but have not found anything useful for this purpose. Quite some time ago I have had difficulty distributing a sum over the elements of its expression; this was answered here and involved a custom function.

Does a package exist that has these kinds of conversions, or do I need to roll my own? It seems a general enough issue that I would expect functions for this to exist.

TIA,

Mac Dude

Hi,

  I have the following input in order to obtain the dimension of an array, by means of the values has been assigned

with(ArrayTools):
with(LinearAlgebra):
f[1]:=1:
f[2]:=2:
nops(f);
Size(f);
Dimension(f);

  The result is 

---

1
[ 1 1 ]
Error, invalid input: LinearAlgebra:-Dimension expects its 1st argument, A, to be of type {Matrix, Vector} or coercible via `~Simplify`, but received f

 ---

I cannot get number "2", which is expected. Is there any way to obtain that? I looked for help and mapleprime, without any simple solution ......

Thank you very much!

Hi,

  Suppose I have an array

A[1]:=a;

A[2]:=b;

A[3]:=c;

  I would like to check if an element, e.g. "c", belong to this array. I can contrsuct a "for... end do" command to compare each element and/or construct a subroutine. 

  Is there any build-in function in maple can do that? Perferably return true/false

Thank you!

I want to compute the following solve:

C:=A, B, F, H(It has 4 unknowns):

V:=R,Y,E,I (It has 4 equations):

solve({V},{C});

By hand calculations I just found that the solve result is real ,but in maple there is no solution and no error (the maple ignores to solve this equation !!!) 

can anybody help me to find the solve soltuion ?

Thank you 

H. Kabir