How to count the size of a variable (upper and lower bound) in Genetic Algorithm

Having 2 objective functions, thermal Eff and Net work output and the variables are P2 with a range 6 to 19 (P2 = 6......13bar) and T3 with a range 930 to 980 (T3 = 930..... 980K). The lower bound has LB = [6 930] and UB = [13 980] what is the number of decision variable i used variable = 2 but is given me error. Can any one explain much better on how to count it and also how to use it in GA. Here is the code....................... Thank you for your kind support

[Geoff Hayes]

Gali - please copy and paste the full error message to your question. Also, attach your code using the paperclip button.

[Gali Musa]

this is the error

Subscripted assignment dimension mismatch. Error in evaluate_objective (line 134) f(1) = Net_Work_out;

Error in initialize_variables (line 80) f(i,V + 1: K) = evaluate_objective(f(i,:), M, V);

Error in nsga_2 (line 126) chromosome = initialize_variables(pop, M, V, min_range, max_range);