粒子群算法代码，一种搜寻最优解的算法。它没有遗传算法的"交叉"(Crossover) 和"变异"(Mutation) 操作，它通过追随当前搜索到的最优值来寻找全局最优。(Particle swarm algorithm, a search algorithm for optimal solutions. It does not have the "Crossover" and "Mutation" operation