下图所示传染病传播过程绿色正常，红色为传染病，蓝色为恢复(并免疫) importnumpyasnpimportrandomimportmatplotlib.pyplotasplt % matplotlibinlineimportnet 小世界网络defsmall_world(n，d，a ) :random.seed ) 1024 ) a=NP.zeros ) () n， n ) forIinrange(n ) :t=0whilet ) d/2 ) : a [ I ] [ I-(t1 )=1a [ I-(t1 ) [ I ]=1t=1foriinrange ] ) 1 [I-(T1 ) ]=0a [ I-(t1 ) ] ) I )=0target (N-1 ) ) whilea [ I ] [ target ]==1or target==I : target=randd 初始化零号患者defpatient_zero(n，num ) 3360 infecters=rannancters num (infect status=NP.zeros (n， int ) for i in Infecters:撒娇的万宝路I ) i]=1 return InfectStatus#感染过程def infect(A ) a，s， beta gamma=0) :n=len(a ) forIinrange(n ) :ifs(I )==1andrandom.random )=gamma 3360 s [ I ]=2if sum (s ) 3360 ifs [ I ]==0: forjinrange (n ) :ifa[I](j )==1ands[j]==1andrandom.random )=beta3360s[I]。 N0，beta，gamma，plot=true(:n=len ) a ) S=patient_zero(N ) n， N0 ) if plot : g=NX.from _ numpy _ matrix (a ) pos=nx.kamada_kawai_layout(g ) g ) nodesize=[ ] maxsize=axis=0) ) ifmaxdegree==min degree : nodesize=[ minsizeforiinrange (len (a ) ] else 3360 fornodeing 3360 size=(NP (MP ) (maxsize-minsize ) minsizenodesize.append(size ) result=[ ] time=0while true 3360 if plot 330 ' b ' ] colors=[ cmap [ CMP ] 20 ) ]NX.draw_NetWorkx_nodes ) g，pos=pos alpha=0.6 ) NX.Draw_NetWorkx_Edges(g，pos=pos，with _ labe ) alpha=0.3 ) PLT.title(time={} ).format (time ) ) (PLT.savefig ) ) }.png ).format ) str ) time ).z fill (4sususte Beta，Gamma ) time=1returnNP.Array(result ) #主程序c=small _ world (1000，4，0.2 ) result=sir(c，2，0.3 )