Introduction to the Modeling and Analysis of Complex Systems

444 CHAPTER 19. AGENT-BASED MODELSn = 1000 # number of agentsw = 100 # number of rows/columns in spatial arrayk = 1 # rate of cAMP decayDc = 0.001 # diffusion constant of cAMPDh = 0.01 # spatial resolution for cAMP simulationDt = 0.01 # time resolution for cAMP simulationf = 1 # rate of cAMP secretion by an agentclass agent:passdef initialize():global agents, env, nextenvagents = []for i in xrange(n):ag = agent()ag.x = randint(w)ag.y = randint(w)agents.append(ag)env = zeros([w, w])nextenv = zeros([w, w])def observe():global agents, env, nextenvcla()imshow(env, cmap = cm.binary, vmin = 0, vmax = 1)axis(’image’)x = [ag.x for ag in agents]y = [ag.y for ag in agents]plot(y, x, ’b.’) # x and y are swapped to match the orientation of envdef update():global agents, env, nextenv