Q1: The Matlab files provided don’t work. The optimal point found by fmincon is different from the one given on the web site. Moreover, the value of δ remains at its initial value.
A1: Using fmincon, the design variables have to be scaled, i.e. the range of variation of each design variable has to be changed from the min and max values to zero and one. So you have to modify the opt.m script and mycon.m, and myfun.m functions. Some methods such as Genetic Algorithm don’t need scaling.