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Hi all,

I am trying to implement boundary conditions in MAPLE, but I don't know how to implement them,  I am attaching a maple file for your kind comments.  An example of similar kind will be of real help.

Thanks in advance

A.Q

Soton

mapleprimes1.mw

 Have to solve and ODE in the domain of [-infnity +infinity ] via specific analytical method but due to some restrictions it could not be solved. In order to solve it, I have separated the domain into [-infinity 0 ] and [0 infinity]. So, I have to add some boundary values at x=0 to the problem. Assuming the solution of the mentioned ODE in  [-infinity 0 ] is g(x) and in [0 infinity]  is f(x), I added the boundary values of f(0)=g(0)=a and f ' (0)=b and obtained f(x...

i came into some questions when i wanted to solve a pde systerm as follows:

> pde := diff(u(x, y), y, y, y, y) = 0;
> sys := [pde, u(x, 0) = 0, u(x, a) = F0, (D[`$`(2, 2)](u))(x, 0) = 0, (D[2, 2](u))(x, a)-beta*(D[2](u))(x, a) = 0];
> pds := pdsolve(sys);
%;
Error, (in pdsolve/sys/info) found functions with same name but depending on different arguments in the given DE system: u(x, a), u(x, y). It is required an indication of the dependent variables

Hello all, I am wondering if anyone knows how to impose a finite value boundary condition to solve an ordinary differential equation? Specifically, suppose that the solution Maple obtains to an ordinary differential equation is y(x)=-2*x^2+C1*ln(x), C1 being a constant. Given that y(x) must be finite when x=0, then C1 has to be zero. Is there a way to implement this condition when setting up to solve the ODE in Maple, i.e. dsolve({ODE, ICs}, y(x), options)? Many thanks for your help!

i'm trying to solve a sysem of pde, but i get this error 

Error, (in PDEtools:-Library:-NormalizeBoundaryConditions) unable to isolate the functions {x(0, z, r), x(t, z, 0.5e-2), xeq(t, z, 0.5e-2), y(0, z, r), y(t, 0, r)} in the given boundary conditions {x(0, z, r) = 0, x(t, z, 0.5e-2) = xeq(t, z, 0.5e-2), y(0, z, r) = 0, y(t, 0, r) = 0}
> 

> restart; with(PDEtools);
[CanonicalCoordinates, ChangeSymmetry, CharacteristicQ, 

  CharacteristicQInvariants,...

I have a region x^2 + y^2 <= 1 and y>=0. It's temperature function is f(x,y) x^2 - 2y^2 + x + y. How do I find the max and min temperatures on the lower boundary y=0?

I took the derivatives with respect to x and with respect to y such that:

fx:=diff(f(x,y),x);

fy:=diff(f(x,y),x);

Then I used fsolve({fx=0, fy=0},{x,y}) which game me (-0.5, 0.25)

Is there really only one critical point on that lower bound...

I tried to solve a non linear coupled boundary value problem in MAPLE using DSolve command. The code is :

alias(eta = e, theta = t)

Eq[1] := 5*(diff(F(e), `$`(e, 3)))+(m+3)*F(e)*(diff(F(e), `$`(e, 2)))-(2*m+1)*(diff(F(e), e))^2-(4*m+2)*H(e)-(m-2)*e*(diff(H(e), e)) = 0

Eq[2] := diff(H(e), e) = t(e)

Eq[3] := 5*(diff(t(e), `$`(e, 2)))/Pr-(m+3)*F(e)*(diff(t(e), e))-5*m*(diff(F(e), e))*t(e) = 0

BCs := [F(0), (D(F))(0), (D(F))(infinity), t(0)-1, t(infinity), H(infinity)]

I was trying to solve a PDE with boundary conditions and maple 15 didn´t give no answer. 

Is there something wrong? I'm just trying to solve a textbook problem om electrodynamics in maple.

Hi. Solving a problem of non-linear oscilations of thin string I met a PDE with unusual bcs at the right side of the string: 
 , where phi is known function. Can...

Hi

I'm solving a differential equation which has a boundary at infinity, when I add this third condition it returns nothing. Of course I it's easy to solve by hand but it should be done in a loop. can you give me a hint on this?

Thanks

Hi all,

I have a set of two coupled PDEs and Maple keeps giving me invalid initial/boundary conditions. I really don't know how to fix it. Attached is my worksheet. Please help me out.

Thank you

2dcase.mw

Hi,

I am trying to solve the following system of ODE's given some initial and final conditions.

Hello,

I am going to solve 2D Laplace equation for function Φ(x,y) in a rectangule which has a*b dimension, yet its boundary condition, at least for me, is rather complex. Here it is:

d/dx(Φ)=0  at  x=0 , x=a

Φ=1  at  0<x<a/2 , y=0   

d/dy(Φ)=0  at a/2<x<a , y=0

Hi,

I am trying to solve a system of PDEs numerically and having following error

Error, (in pdsolve/numeric/plot3d) unable to compute solution for t>HFloat(0.0):
solution becomes undefined, problem may be ill posed or method may be ill suited to solution

Please have a look at attached worksheet and help me out.

Moreover, I want to include boundary conditions are not normal to the boundary. Anyone knows how to do so? Any help would be appreciated.