//clc()
x = [0.25,0.75,1.25,1.75,2.25];
y = [0.28,0.57,0.68,0.74,0.79];
a0 = 1;
a1 = 1;
sr = 0.0248;
for i = 1:5
    pda0(i) = 1 - exp(-a1 * x(i));
    pda1(i) = a0 * x(i)*exp(-a1*x(i));
end
Z0 = [pda0(1),pda1(1);pda0(2),pda1(2);pda0(3),pda1(3);pda0(4),pda1(4);pda0(5),pda1(5)]
disp(Z0,"Z0 = ")
R = Z0'*Z0;
S = inv(R);
for i = 1:5
    y1(i) = a0 * (1-exp(-a1*x(i)));
    D(i) = y(i) - y1(i);
end
disp(D,"D = ")
M = Z0'*D;
X = S *M;
disp(X,"X = ")
a0 = a0 + det(X(1,1));
a1 = a1 + det(X(2,1));
disp(a0,"The value of a0 after 1st iteration = ")
disp(a1,"The value of a1 after 1st iteration = ")