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

I have written a Math App in Maple to create a Math App question in Maple TA.

The app has two tables, a plot area, and text box. The first table provides the data to the students for calculating their answer (and so Editable in the component properties is unchecked). The second table is where the student enters their answers (and so Editable is checked). The text area and plot area are for providing some real time feedback and error checking to the students.

Everything works fine in Maple.

In Maple TA I have tried using both a Math App question type and a Question Designer question type with a Math App inserted. I have tested it in Internet Explorer, Chrome and Firefox.

In all six cases when I click on one of the editable table cells to put in an answer a popup appears with the error message: "Unable to update RTable due to error=TypeError: window.parent.parent.updateRTable is not a function"

I am using Maple 10 and the latest hotfix is SP-002.

What I have worked out so far is that the Maple TA web page is designed so that the Math App sits in an iframe and each table sits in a separate iframe inside that iframe. updateRTable is a function inside the tables iframe that calls the updateRTable on the top level window and if this fails gives the error message above.

The top level window includes the file /maplenet/js/worksheet.js, which includes the function updateRTable.

How do I fix this error?

Thanks

hi.I want to dsolve set of nonlinear equations with one unknown parameter ...is this possible with dsolve rule.in matlab this possible with bvp4c rule..please help me for this problem.if we should another rule please attached file reform.Thanks alot12.mw

I need to solve a set of equations but changing a constant each time.

For example, x+by=0, bx-y=10 where b=10,20.

I don't want to put it in a loop because, in loop, the equations are solved repeatedly. I want Maple to solve it only once and substitute b values automatically since I want to solve big set of equations faster.

Is there any option in Maple to do so with a single command

I know how we can add a member to a mathematical set ,for example :

C := NULL;

C := C, V, B, X;

print(C)

V, B, X

but, my problem is that how we can subtract a member from the defined set ?

Thanks,

hi.how i can chose a minimum and positive answer of different answer in solve rule...

my program attached below.for example at this , the second answer should be selected as 1.965392881*10^9 ,that is the minimum and posetive among other...

thanks alot

11.mw

Dear all,

I am trying to solve the following partial differential equation (transport or advection equation) with given initial and boundary conditions:

restart: with(PDEtools):
sys := [v*diff(u(x,t), x) + diff(u(x,t), t) = 0, u(x,0) = exp(-x), u(0,t) = sin(t)];
pdsolve(sys);

But it does not work. The solution is (or should be): 

u(x, t) = exp(t*v-x)+Heaviside(t-x/v)*(sin(t-x/v)-exp(t*v-x))

I think the reason is that the interval for t (in [0, inf)) and x (in [0, 1]) is not specified. On the other hand, this works:

restart: with(PDEtools):
sys := [diff(u(x, t), t) = diff(u(x, t), x, x), u(0, t) = 0, u(1, t) = 0, u(x,0) = f(x)];
sol := pdsolve(sys);

How can I solve a PDE like the transport equation with given initial AND boundary conditions?

Thanks a lot

I want to display calculation steps by maple like this

k=a+b*c=2+4*4=9

How can I do so that when I enter k:=a+b*c (the value of a,b,c have been assigned) and it can show the substitution process and display the result like this

The font size in the output pane of the standard interface, interactive debugger is really, really small and I can't figure out how to increase it. (Other than drop my screen resolution from its native 2560x1440, which makes it bigger but "fuzzier" - not a huge improvement for tired eyes!!)

I started to notice strange things happening to Maple help pages lately when I google something. I think someone is changing them from inside Maplesoft? Now they look hard to read since I see text below another text and also can't copy it to retype it in my notebook since the syntax is not even valid. Here is a screen shot

http://www.maplesoft.com/support/help/maple/view.aspx?path=FileTools%2fText%2fOpen

I thought at first my browser was playing games on me. But I tried it with firefox and Chrome and after refreshing, and the pages still look mangled like the above.

Since I find it hard to believe someone at Maplesoft will make help pages like the above on purpose, where text falls below the line and it not even possible to interpret it when one wants to copy it, since the syntax is not even valid Maple syntax, I would have to imagine there is a bug somewhere inthe help pages generation.  But if so, someone must have seen it before me. I can't be the only person in the world who is googling Maple help.

This is why I am asking.

Is everyone seeing the same thing I am seeing? I am on windows 7, using Latest browsers.