说明：  基于matlab的visek模型的数值模拟，可以修改粒子的数量，每步迭代的权重与速度，并将最后各例子的位置及欲动的速度用箭头表示出来，对其他类似作图有一定的借鉴意义。
(A matlab code for visek model. the user may change the number of particles, and the related velocity and weight. it gives the final places and velocities of each particle, and could be used for other similar simulations)