Fixed Point Iteration technique for nonLinear ODEs

I am trying to solve u''=(u-4)./(5-u)-exp(3*x)

Is this code correct

%% Housekeeping clc clear all format compact n = 100; tol = 10^-4; x = linspace(0,1,n)'; a = linspace(0.1,1,10)'; b = ones(10,1)'; S=(n-1)^-1*(gallery('tridiag',n,-1,2,-1)); %One Line Generation of Sparse Matrix A.

%% Anonymous Functions kappa=10^-4 ;

A=@(x,u) (u-4)./(5-u)-exp(3*x) ; B=@(x,u) -(u+kappa).^-1.5-x.*exp(4*x); C=@(x,u) -(u+kappa).^-7-x.*exp(4*x); %% The Fixed Point Method A format compact d = 1; i = 0; u = zeros(n,1);

while d>tol && i<2 unew = -(S\((A(x,u)))); d1=max(abs(u-unew)); d2=(abs(S*unew+A(x,unew))); d=max(abs(d1-d2)); u=unew; i=i+1; end fpAi=i fpAd=d

figure; % plot (x,u,'-r*'); plot (x,u); title('Fixed point method for Equation A') xlabel('X axis'); ylabel('u(x)');