Error with Cheb function

Where the ODE is

with boundary condition

y(1)=sin(1)

D = [1/pi*3 ,1];
N = chebop(D); 
N.lbc = [1];
N.rbc = 1 - sin(1);
N.op = @(t,x,y) diff(y,2) + (2/x)*diff(y,1) + (1/(x^4))*y;
[x, y] = N\0;
plot([x, y]);

[Walter Roberson]

What difficulty are you experiencing?

[Walter Roberson]

https://www.mathworks.com/matlabcentral/answers/802026-how-to-use-chebop-function#answer_674996

[Chala Kedir]

@Walter Roberson I couldn't plot the output, please if you could help me, it would help me a lot

[Walter Roberson]

What error message are you getting, at what line?

Have you installed the Chebfun package? https://www.mathworks.com/matlabcentral/fileexchange/47023-chebfun-current-version

[Chala Kedir]

@Walter Roberson

this is the error message I get

Error using chebop/linearize
Failed to evaluate operator on the initial guess passed (or the one constructed
by CHEBOP). A potential cause might be division by a zero CHEBFUN. Please supply
a valid initial guess via the 'init' field of the CHEBOP.
Error in chebop/solvebvp (line 109)
[L, residual, isLinear] = linearize(N, u0, x);
Error in  \  (line 56)
    [varargout{1:nargout}] = solvebvp(N, rhs, varargin{:});
Error in untitled (line 6)
[x, y] = N\0;

[Torsten]

Are you sure about your D ?

Shouldn't it be

D = [1, 1/3*pi];

?

Answer 1

[Bhavana Ravirala]

Hi,

The error you received indicates that the operator fails to evaluate the initial guess. To resolve this error, we can assign the initial guess with the boundary conditions.

N.init = [0; sin(1)];

Hope this helps!!