小世界网络模拟，首先从n个顶点环形开始，每个顶点由无向边连接最近的k个顶点，疾病根据传染率r进行传播，并计算临界值rhalf-calculate of smallword networks

复杂网络中小世界网络生成程序，可以用matlab生成制定聚类系数 连接概率和平均最短路径长度的经典小世界网络(A small world network generating program for complex networks, which can be used to generate a classical small world network with clustering coefficients, connection probabilities and average sho