Frid

function [y] = Fred_II_Rect(K,f,a,b,h)
x = a:h:b;
n = size(x,2);
wt = 1/2;
wj = 1;

A = zeros(n);
for i = 1:n
    A(i,1)= h*wt*K(x(i),x(1));
    for j=2:n-1
    	A(i,j)= h*gtwj*K(x(i),x(j));
    end;
    A(i,n)= h*wt*K(x(i),x(n));
     A(i,i)= A(i,i)+ 1;
end;

B = zeros(n,1);
for j=1:n
    B(j,1) = f(x(j));
end;
y = A\B;

main

close
all clear
all clc
format long;
N = 10;
h = 1 / N;
a = 0;
b = 1;
epsilon = 0.01;
K = @(x1,s)(x1 + s)*epsilon;
f = @(x1)x1;

y_approx1 = Fred_II_Rect(K,f,a,b,h);

epsilon = 0.005;
K = @(x1,s)(x1 + s)*epsilon;
y_approx2 = Fred_II_Rect(K,f,a,b,h);

hold on
plot(a:h:b, y_approx1);
plot(a:h:b, y_approx2);