PFC生成不规则cluster,并将cluster中的ball随机分成两大部分,添加不同的组别,请给出代码
时间: 2024-09-13 20:03:57 浏览: 74
在Python中,我们可以使用`PFC`(Population-based Clustering)算法,例如DEAP(Distributed Evolutionary Algorithms in Python)库中的粒子群优化(Particle Swarm Optimization, PSO)来创建不规则的簇,然后随机分配球到两个组别。这是一个简化版本的代码示例:
```python
from deap import base, creator, tools
import numpy as np
# 创建基础结构
creator.create("FitnessMax", base.Fitness, weights=(1.0,))
creator.create("Individual", list, fitness=creator.FitnessMax)
def distance(x, y):
# 计算两点之间的距离
return np.linalg.norm(np.array(x) - np.array(y))
def pso_cluster(data, n_clusters, max_iter=100):
# 初始化参数
pop_size = len(data)
w = 0.7 # 学习因子
c1, c2 = 2.0, 2.0 # 社会和认知权重
particles = [ Individual(random.sample(data, n_clusters)) for _ in range(pop_size) ]
# 将数据集转换为适应度函数
toolbox = base.Toolbox()
toolbox.register("evaluate", evaluate_clusters, data=data, distance=distance)
toolbox.register("mate", tools.cxTwoPoint)
toolbox.register("mutate", tools.mutShuffleIndexes, indpb=0.1)
toolbox.register("select", tools.selTournament, tournsize=3)
# 进行PSO迭代
best_particle = None
for gen in range(max_iter):
offspring = toolbox.select(particles, len(particles))
offspring = [toolbox.clone(ind) for ind in offspring]
for i, part in enumerate(offspring):
r1, r2 = np.random.rand(), np.random.rand()
part.position = w * part.position + c1 * r1 * (particles[np.argmax(part.best_pos)].position - part.position) + \
c2 * r2 * (particles[np.argmax(toolbox.evaluate(part.position))].position - part.position)
part.best_position = toolbox.mate(part.position, part.best_position)
part.best_position.fitness.values = toolbox.evaluate(part.best_position)
if part.fitness.values > part.best_fitness.values:
part.best_fitness.values = part.fitness.values
# 比较当前最佳解与全局最优解
if not best_particle or part.best_fitness.values < best_particle.best_fitness.values:
best_particle = part
return best_particle.cluster, np.split(data, [best_particle.best_fitness.values[0].n_clusters])
def evaluate_clusters(partition, data, distance):
# 根据簇中心的距离计算适应度值
cost = sum(distance(partition[i], np.mean(data[partition[i]], axis=0)) for i in range(len(partition)))
return [-cost]
# 使用数据集并分组
data = ... # 假设这是你的数据
clusters, group_labels = pso_cluster(data, 2)
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