用netlogo写一个蚁群算法模型
时间: 2024-05-07 14:22:34 浏览: 141
好的,以下是一个简单的蚁群算法模型的 NetLogo 代码:
```
globals [
pheromone-map ; 信息素地图
]
turtles-own [
path ; 蚂蚁的路径
path-length ; 蚂蚁的路径长度
]
to setup
clear-all
reset-ticks
; 初始化信息素地图
set pheromone-map matrix:make-constant 50 50 0
; 创建蚂蚁
create-turtles 10 [
setxy random-xcor random-ycor
set color red
]
end
to go
ask turtles [
; 选择下一个节点
let next-node select-next-node
; 更新路径和路径长度
set path lput next-node path
set path-length path-length + distance next-node
; 在当前节点释放信息素
let current-node first path
set pheromone-map matrix:set pheromone-map current-node pheromone-map current-node + (1 / path-length)
; 如果到达了终点,则返回起点并更新信息素
if next-node = min-one-of nodes [distance current-node ?] [
set path lput min-one-of nodes [distance current-node ?] path
set path-length path-length + distance current-node min-one-of nodes [distance current-node ?]
set color black
set path []
set path-length 0
update-pheromone-map
]
; 移动到下一个节点
move-to next-node
]
tick
end
to select-next-node
let current-node patch-here
let next-node nobody
let max-pheromone 0
; 选择下一个节点
ask neighbors [
if not member? self path [
let p pheromone-map current-node self
if p > max-pheromone [
set max-pheromone p
set next-node self
]
]
]
; 如果没有可行的节点,则返回起点
if next-node = nobody [
set next-node min-one-of nodes [distance current-node ?]
]
; 返回下一个节点
report next-node
end
to update-pheromone-map
ask patches [
; 信息素挥发
set pheromone-map self pheromone-map self * 0.9
; 信息素加强
ask turtles [
if member? self path and first path = self and self = patch-here [
set pheromone-map self pheromone-map self + (1 / path-length)
]
]
]
end
```
这个模型中,每只蚂蚁都会选择下一个节点,并在当前节点释放信息素。如果蚂蚁到达终点,则返回起点并更新信息素。每一轮迭代结束后,所有信息素都会挥发一定的量,同时在路径上的蚂蚁会加强路径上的信息素。通过不断迭代,蚂蚁会逐渐找到最优路径。
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