# Step5: 多层次代理的交互 目前为止，我们编写的代理行为都是代理本身来控制，那么如何实现代理族B来控制代理族A的行为呢？比如，我们为建筑添加一个人群管控的功能，当人群进入建筑时，其行为受到管控，直到建筑允许放行，才能从建筑中出来，要实现这样的复杂交互，我们要做的有以下几点： * 为建筑添加人群管控行为： **`let_people_leave`** 和 **`let_people_enter`**。 * 在**建筑族**中创建**人群族的子族群** **`people_in_building`** ，当人群进入建筑后，变为建筑族的一员，但保留了人群族的所有属性。 ``` species building { ... //在建筑族中添加人群族的子族群people_in_building，其行为为空 species people_in_building parent: people schedules: [] { } ... //定义人群进入建筑的行为 reflex let_people_enter { //捕获进入建筑的人群，将其改为子族群people_in_building的一员 capture (people inside self where (each.target = nil)) as: people_in_building; } //定义人群离开建筑的行为 reflex let_people_leave { //计算进入建筑的人的停留时长 ask people_in_building { staying_counter <- staying_counter + 1; } //以staying_counter / staying_coeff的概率释放子族群people_in_building的代理至世界代理中的people族 release people_in_building where (flip(each.staying_counter / staying_coeff)) as: people in: world { //其目标为随机一栋建筑的任意地点 target <- any_location_in(one_of(building)); } } ... } ``` > **`schedules`：**可以理解为时间调度表，将schedules设置为空，则代理行为均失效。 现在，我们将建筑的显示方式改为： * 建筑中没有人时显示为灰色 * 建筑中感染人数比例小于0.5时显示为绿色 * 建筑中感染人数比例大于0.5时显示为红色 ``` species building { //统计建筑中感染人群的数量 int nb_infected <- 0 update: self.people_in_building count each.is_infected; //统计建筑中所有人的数量 int nb_total <- 0 update: length(self.people_in_building); //更改建筑显示方式 aspect default { draw shape color: nb_total = 0 ? #gray : (float(nb_infected) / nb_total > 0.5 ? #red : #green) border: #black depth: height; } } ``` 因为人群分离出了子族群，因此我们在全局定义中统计感染人数的方法也需要更新。 ``` global { ... //返回people_in_building族的列表 list list_people_in_buildings update: (building accumulate each.people_in_building); //统计people族和所有people_in_building族中感染人数 int nb_people_infected <- nb_infected_init update: (people + list_people_in_buildings) count (each.is_infected); ... } ``` > **`accumulate`**：accumulate 和 collect 类似，区别在与accumulate 返回的是列表，collect 返回值可以是任何容器。 ![6.5.1 在建筑族中创建人群子族](/files/-MgZ3MPF5VQf41PZpGSP) 本节完整代码如下： ``` model SI_city global { //模拟设置 float step <- 1 #minutes; //小于7点或者大于20点为夜 bool is_night <- true update: current_date.hour < 7 or current_date.hour > 20; //载入GIS数据 file roads_shapefile <- file("../includes/road.shp"); file buildings_shapefile <- file("../includes/building.shp"); //将全局代理形状设置为包括所有道路的矩形 geometry shape <- envelope(roads_shapefile); //初始人群数量 int nb_people <- 500; //人群速度 float agent_speed <- 5.0 #km/#h; //感染距离 float infection_distance <- 2.0 #m; //感染概率 float proba_infection <- 0.05; //初始感染人数 int nb_infected_init <- 5; //路网 graph road_network; //定义staying_coeff，随着时间递增，并在9点、12点、18点时数值最小 float staying_coeff update: 10.0 ^ (1 + min([abs(current_date.hour - 9), abs(current_date.hour - 12), abs(current_date.hour - 18)])); //返回people_in_building族的列表 list list_people_in_buildings update: (building accumulate each.people_in_building); //统计people族和所有people_in_building族中感染人数 int nb_people_infected <- nb_infected_init update: (people + list_people_in_buildings) count (each.is_infected); //统计未感染人数 int nb_people_not_infected <- nb_people - nb_infected_init update: nb_people - nb_people_infected; //感染率为感染人数/总人数 float infected_rate update: nb_people_infected/nb_people; //初始化 init { create road from: roads_shapefile; create building from: buildings_shapefile; //初始化路网 road_network <- as_edge_graph(road); create people number:nb_people { speed <- agent_speed; location <- any_location_in(one_of(building)); } //在人群族中随机寻找nb_infected_init人 ask nb_infected_init among people { //将其感染状态设置为真 is_infected <- true; } } //当感染率为1时，停止模拟 reflex end_simulation when: infected_rate = 1.0 { do pause; } } //创建建筑族 species building { //在建筑族中添加人群族的子族群people_in_building，其行为为空 species people_in_building parent: people schedules: [] { } //统计建筑中感染人群的数量 int nb_infected <- 0 update: self.people_in_building count each.is_infected; //统计建筑中所有人的数量 int nb_total <- 0 update: length(self.people_in_building); //为建筑添加高度属性 float height <- rnd(10#m, 20#m) ; //定义人群进入建筑的行为 reflex let_people_enter { //捕获进入建筑的人群，将其改为子族群people_in_building的一员 capture (people inside self where (each.target = nil)) as: people_in_building; } //定义人群离开建筑的行为 reflex let_people_leave { //计算进入建筑的人的停留时长 ask people_in_building { staying_counter <- staying_counter + 1; } //以staying_counter / staying_coeff的概率释放子族群people_in_building的代理至世界代理中的people族 release people_in_building where (flip(each.staying_counter / staying_coeff)) as: people in: world { //其目标为随机一栋建筑的任意地点 target <- any_location_in(one_of(building)); } } //更改建筑显示方式 aspect default { //无人为灰，感染率小于0.5为绿，感染率大于0.5为红 draw shape color: nb_total = 0 ? #gray : (float(nb_infected) / nb_total > 0.5 ? #red : #green) border: #black depth: height; } } //创建道路族 species road { //为道路增加属性display_shape，其值为原图形增加2m geometry display_shape <- shape + 2.0; aspect default { //更改默认显示图形为display_shape，设置道路高度为3m draw display_shape color: #black depth: 3.0; } } //人群族定义 species people skills: [moving] { //是否感染 bool is_infected <- false; //增加属性目标点和stay_counter point target; int staying_counter; //当没有目标时停留 reflex stay when: target = nil { //staying_counter随时间递增 staying_counter <- staying_counter + 1; //以staying_counter / staying_coeff的概率将目标变为随机建筑中的任意地点 if flip(staying_counter / staying_coeff) { target <- any_location_in (one_of(building)); } } //当有目标时开始移动 reflex move when: target != nil{ //沿着路网向目标点出发 do goto target: target on: road_network; //达到目标点时将目标设为空值，将staying_counter清零 if (location = target) { target <- nil; staying_counter <- 0; } } //当代理人被感染时 reflex infect when: is_infected { //寻找与其相距infection_distance的其他代理 ask people at_distance infection_distance { //以proba_infection的概率感染 if (flip(proba_infection)) { is_infected <- true; } } } //默认显示设置 aspect default { //显示为半径为5的圆形，感染者为红色，未感染者为绿色 draw circle(5) color: is_infected ? #red : #green; } //增加3D显示方式 aspect sphere3D{ //因为道路高度为3m，此处注意高度为原高度+3m draw sphere(3) at: {location.x,location.y,location.z + 3} color:is_infected ? #red : #green; } } //实验设置 experiment main_experiment type: gui { //参数设置 parameter "Infection distance" var: infection_distance; parameter "Proba infection" var: proba_infection min: 0.0 max: 1.0; parameter "Nb people infected at init" var: nb_infected_init; //输出 output { //增加当前时间的数据监管器 monitor "Current hour" value: current_date.hour; //增加当前感染人数的数据监管器 monitor "Infected people rate" value: infected_rate; //显示设置 display map { species road ; species building ; species people ; } //将显示类型设置为opengl display map_3D type: opengl { //设置全局照明，如果是晚上亮度为50，白天为255 light 1 color:(is_night ? 50 : 255); //添加背景图 image "../includes/soil.jpg"; //设置显示方式 species road; species people aspect: sphere3D; //为建筑添加50%的透明度 species building transparency: 0.5; } //增加感染人数和未感染人数的折线图 display chart refresh: every(10#cycles) { chart "Disease spreading" type: series style: spline { data "susceptible" value: nb_people_not_infected color: #green; data "infected" value: nb_people_infected color: #red; } } } } ``` --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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