Asking for Matlab Code for boundary value problem using finite element method ?

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Let us consider the following problem:
I want to write Matlab code using finite element method in order to solve the above problem but I didn't succeed because am not familiar with that Matlab programming however I have tried to give such code below which it dosn't work ,any help ?
Here is my attempt. CODE
-u’’+6 u(x) = f(x), -1 <= x <=1, u(-1)=u(1)=0 %
% Input: x, Nodal points %
% Output: U, FE solution at nodal points %
% %
% Function needed: f(x)=(-4x^2-6)exp(x^2). %
% %
% Matlab functions used: %
% %
% hat1(x,x1,x2), hat function in [x1,x2] that is 1 at x2; and %
% 0 at x1. %
% %
% hat2(x,x1,x2), hat function in [x1,x2] that is 0 at x1; and %
% 1 at x1. %
% %
% int_hat1_f(x1,x2): Contribution to the load vector from hat1 %
% int_hat2_f(x1,x2): Contribution to the load vector from hat2 %
%
M = length(x);
for i=1:M-1,
h(i) = x(i+1)-x(i);
end
A = sparse(M,M); F=zeros(M,1); % Initialization
A(1,1) = 1; F(1)=0;
A(M,M) = 1; F(M)=0;
A(2,2) = 1/h(1); F(2) = int_hat1_f(x(1),x(2));
for i=2:M-2, % Assembling element by element
A(i,i) = A(i,i) + 1/h(i);
A(i,i+1) = A(i,i+1) - 1/h(i);
A(i+1,i) = A(i+1,i) - 1/h(i);
A(i+1,i+1) = A(i+1,i+1) + 1/h(i);
F(i) = F(i) + int_hat2_f(x(i),x(i+1));
F(i+1) = F(i+1) + int_hat1_f(x(i),x(i+1));
end
A(M-1,M-1) = A(M-1,M-1) + 1/h(M-1);
F(M-1) = F(M-1) + int_hat2_f(x(M-1),x(M));
U = A\F; % Solve the linear system of equations
return
[SL: formatted code as code]
  1 Comment
Steven Lord
Steven Lord on 3 Sep 2020
What does "dosn't [sic] work" mean?
  • Do you receive warning and/or error messages? If so the full and exact text of those messages (all the text displayed in orange and/or red in the Command Window) may be useful in determining what's going on and how to avoid the warning and/or error.
  • Does it do something different than what you expected? If so, what did it do and what did you expect it to do?
  • Did MATLAB crash? If so please send the crash log file (with a description of what you were running or doing in MATLAB when the crash occured) to Technical Support using the telephone icon in the upper-right corner of this page so we can investigate.
Also it will be impossible for us to try to run your code to investigate what's going on since you have not provided the int_hat1_f and int_hat2_f functions.

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