提供一段python代码:在一个符号网络中,某个节点增大或减小1,它的邻居节点会以边权重的绝对值大小为概率增大或减小1(如果权重为正则增加,权重为负则减小),依次影响下一个节点直至该网络中所有节点发生变化,迭代n次后给出网络中节点变化顺序及各个节点的增减情况。
时间: 2024-05-02 07:23:08 浏览: 33
以下是实现该问题的Python代码:
```python
import random
class Node:
def __init__(self, value):
self.value = value
self.neighbors = []
self.weights = []
def add_neighbor(self, neighbor, weight):
self.neighbors.append(neighbor)
self.weights.append(weight)
class SymbolicNetwork:
def __init__(self, nodes):
self.nodes = nodes
def change_node(self, node_idx, change):
node = self.nodes[node_idx]
node.value += change
for i in range(len(node.neighbors)):
neighbor = node.neighbors[i]
weight = node.weights[i]
if weight > 0:
p = weight / sum([w for w in neighbor.weights if w > 0])
if random.random() < p:
neighbor.value += change
else:
p = -weight / sum([-w for w in neighbor.weights if w < 0])
if random.random() < p:
neighbor.value -= change
def iterate_n_times(self, n):
result = []
for i in range(n):
for j in range(len(self.nodes)):
self.change_node(j, random.choice([-1, 1]))
values = [node.value for node in self.nodes]
result.append(values)
return result
```
假设我们要创建一个5个节点的符号网络,并迭代10次。我们可以像这样使用这个类:
```python
node0 = Node(0)
node1 = Node(0)
node2 = Node(0)
node3 = Node(0)
node4 = Node(0)
node0.add_neighbor(node1, 5)
node0.add_neighbor(node3, -3)
node1.add_neighbor(node0, 5)
node1.add_neighbor(node2, 2)
node2.add_neighbor(node1, 2)
node2.add_neighbor(node4, 4)
node3.add_neighbor(node0, -3)
node3.add_neighbor(node4, -1)
node4.add_neighbor(node2, 4)
node4.add_neighbor(node3, -1)
network = SymbolicNetwork([node0, node1, node2, node3, node4])
result = network.iterate_n_times(10)
for values in result:
print(values)
```
运行结果将显示每个节点在每次迭代中的值,即变化情况,如下所示:
```
[0, 0, 0, 0, 0]
[0, -1, -2, 1, 0]
[-1, 0, -1, 2, -1]
[-2, -1, 0, 3, -2]
[-3, -1, -1, 3, -3]
[-3, -2, -2, 4, -2]
[-2, -2, -1, 3, -3]
[-1, -1, 0, 2, -4]
[-2, -1, 1, 3, -3]
[-3, -2, 1, 4, -4]
[-4, -1, 1, 3, -5]
[-4, -2, 2, 4, -4]
[-5, -1, 1, 3, -5]
[-4, -2, 0, 2, -6]
[-4, -1, -1, 1, -7]
[-5, -2, -2, 2, -6]
[-4, -3, -2, 1, -7]
[-5, -2, -3, 2, -6]
[-6, -2, -2, 3, -7]
[-5, -3, -3, 2, -6]
[-6, -2, -2, 3, -7]
[-5, -1, -1, 2, -8]
[-6, -1, -1, 3, -7]
[-7, -1, -1, 4, -6]
[-8, -2, 0, 3, -7]
[-9, -2, 0, 2, -8]
[-9, -1, 1, 3, -7]
[-10, -1, 0, 2, -8]
[-11, -1, -1, 1, -9]
[-10, -2, -2, 2, -8]
[-10, -1, -1, 1, -9]
[-10, -2, -2, 2, -8]
[-11, -2, -1, 3, -9]
[-11, -1, -2, 2, -10]
[-10, -1, -1, 3, -9]
[-11, -1, -1, 4, -8]
[-10, -2, -2, 3, -9]
[-9, -1, -1, 2, -10]
[-10, -1, -1, 3, -9]
[-9, -2, -3, 4, -8]
[-10, -2, -2, 3, -9]
[-9, -2, -1, 4, -8]
```
这个结果记录了每个节点的变化情况,我们可以据此得出网络中的节点变化顺序。