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.

Is it possible in Maple to choose the dimensions for a plot? I mean to choose the height and the width of the plot?
For example, to enlarge the plot to the whole width of the maple page? Is it possible?
I need to do this because I have to plot together objects of different dimensions and so the smaller ones look too small, so I would like to enlarge the plot to solve the problem. 

Hi

I have an expression as the following:

exp1:=E(z)*(diff(t(r), r))/(1-nu(z)^2)+E(z)*nu(z)*t(r)/((1-nu(z)^2)*r)+(E(z)*z/(1-nu(z)^2)-(4/3)*E(z)*z^3/(h^2*(1-nu(z)^2)))*(diff(y(r), r))+(E(z)*nu(z)*z/(1-nu(z)^2)-(4/3)*E(z)*nu(z)*z^3/(h^2*(1-nu(z)^2)))*y(r)/r-(4/3)*E(z)*z^3*(diff(p(r), r, r))/(h^2*(1-nu(z)^2))-(4/3)*E(z)*nu(z)*z^3*(diff(p(r), r))/(h^2*(1-nu(z)^2)*r);

I want to replace the following parameter instead of coefficients of t(r), y(r), p(r) and their derivatives as the following:...

I'm trying to substitute a list of equations into an expression as so:

V:=ReSeq([seq(seq(u(t)^r*v(t)^s=y(r,s),r=0..w+e+1),s=0..w+e+1)]); # where ReSeq reverses the order of the sequence

for i from 1 to nops(V)-1 do
N[i]:=algsubs(V[i],N[i-1]);
end do;

where N[0] is a polynomial in u(t) and v(t). But it keeps giving y(1,0)*y(2,0) instead of y(3,0).

i calculate a polynomial as following

yn := f(x) = _C1*hypergeom([-(1/2)*n, 3/2+(1/2)*n], [1/2], x^2)+_C2*hypergeom([2+(1/2)*n, 1/2-(1/2)*n], [3/2], x^2)*x

want to get the polynomial with degree n  for  summation_n_from_0_to_infinity y_n*z^n/n!

such as n = 1 n = 0 n = 3, but above yn is hypergeom, is n represent degree, if so, i use subs, then is finished, if not, how to get polynomial with degree n?

What is the distance between the trigonometrical polynomials of the form a0/2+a1*cos(Pi*x)+b1*sin(Pi*x) and the polynomials of  degree at most 1, ie c0+c1*x, in the Chebyshev metrics on the interval [-1,1] and in the L^2 metrics on the same interval?

I have a set of nonlinear and coupled PDEs for a cable actuated system. I want to transfer this set to a set of ODEs and write it down in Matrix form. I used Galerkin's method and derived the ODEs in discritized form. I have a problem in converting this set of equation into a matrix form like "Mq"+Cq'+Kq=F". The derived equations are very complicated and contains some nonlinear terms. One of the three equations looks like this:

I have been investigating Predator-Prey spatial models, e.g.

Is there a way to select multiple entries in a ListBox component? 

Hi,

    I'm trying to get a component to perform a Fractional Derivative in MapleSim to use in a multibody simulation (as a spring-dash pot component). However, I'm stumped by trying to get the fracdiff function past the custom component code.

• When set to series, the fractional derivative is only accurate near the estimated about point
• When set to LaPlace, it's impossible to perform the transform...

I have a problem.

I solved a problem, but i like to get one solution for one variable.

i send my project.

help me please.21-07-2011_-ecuacion.mw

Dear guys

In my program I have a loop and after some calculation I want to write the results. I use:

" writedata("D:\\arvin\\bao-cmb-h.txt", convert(T, array), float);"

but maple give me an error:

" Error, (in convert/list) object too large "

how can I write my data?

Thanks.

I'm developing an application that I'd like to use elements of an array as parameters in MapleSim components - is there a way to use Maple arrays/vectors in MapleSim?

Also is there a way to open a file and read its contents (data) as the starting point (parameter set) for a MapleSim simulation?

Hi Dr. Kamel Boughrara,

I have a question,  I know phi = B*A, but in code i can't understand a part of it, can you kindly explain it in engineering terms.  

kindly see the attach file for phi.

Second question

why e-->sum(factor(e(t)),n=1..100), wht this means,