Subscript indices must either be real positive integers or logicals.

for i=1:3
    for j=1:4
Lem=alpha(exp(-(XX1(i,:)-Bad_particle(1,j)+1)/(best_particle(1,j)-Bad_particle(1,j)+1)));
    end
    Lemda
end

[madhan ravi]

alpha*(exp(-(XX1(i,:)...
  %  ^

Answer 1

[Walter Roberson]

Your exp() term is being used to subscript the variable alpha but it is unlikely that exp() just happen to work out as exactly an integer.

Perhaps you want to multiply alpha by something.

There is a MATLAB function named alpha ,but it cannot return any values.