Harmony Search as a Metaheuristic Algorithm - Music-Inspired Harmony Search Algorithm: Theory and Applications - page 4

The third component is the randomization, which is to increase the diversity of the
solutions. Although the pitch adjustment has a similar role, it is limited to certain area
and thus corresponds to a local search. The use of randomization can drive the system
further to explore various diverse solutions so as to attain the global optimality.
These three components in harmony search can be summarized as the pseudo code
shown in Figure 1. In this pseudo code, we can see that the probability of randomiza-
tion is

P = 1 − r ,

(4) random accept

and the actual probability of the pitch adjustment is

P = r × r .

(5) pitch accept pa

2.3 Implementation

The above-mentioned three components of the HS algorithm can be easily imple-
mented using any programming language. However, Matlab gives more straightfor-
ward way because it also provides visualization as shown in Figure 2.

Fig. 2. The search paths of finding the global optimal solution (1,1) using the harmony search