Is this what you wanted?
You almost had it. The problem is, you tried to plot the 'Unimodal' with a fixed length of 11 against 'scaling' with a variable length (changing on every iteration). I did it like this:
clear all;
close all;
Unimodal = [28,42,46,49,52,55,58,61,64,68,82];
c = length(Unimodal) ;
a = max(Unimodal) ;
b = min(Unimodal) ;
[~, ~, rank] = unique(Unimodal) ;
w = [0.3,0.4];
for j = 1:length(w)
for i = 1:c
S(i) = Unimodal(i);
R(i) = (S(i)-b)/(a-b);
F(i) = (rank(i)-1)/(c-1) ;
J(i) = w(j)*R(i)+(1-w(j))*F(i) ;
scaling(i,j) = 7 * mat2gray(J(i)); %saving on (i,j) position of scaling
end
end
%plotting outside loop
figure();
plot(Unimodal,scaling);
xlabel('Prices');
ylabel('Expensiveness');
title('Varying in w in Unimodal')
legend('w1','w2');
