Calculus has been used in solving many scientific and engineering problems. For optimization
problems however the differential calculus technique sometimes has a drawback when the
objective function is step-wise discontinuous or multi-modal or when decision variables are
discrete rather than continuous. Thus researchers have recently turned their interests into
metaheuristic algorithms that have been inspired by natural phenomena such as evolution animal
behavior or metallic annealing. This book especially focuses on a music-inspired metaheuristic
algorithm harmony search. Interestingly there exists an analogy between music and
optimization: each musical instrument corresponds to each decision variable musical note
corresponds to variable value and harmony corresponds to solution vector. Just like musicians
in Jazz improvisation play notes randomly or based on experiences in order to find fantastic
harmony variables in the harmony search algorithm have random values or previously-memorized
good values in order to find optimal solution.
