聚类人工蜂群算法python
时间: 2023-10-11 20:08:43 浏览: 89
以下是基于Python的聚类人工蜂群算法的代码示例:
```python
import numpy as np
from sklearn.cluster import KMeans
from sklearn.datasets import make_blobs
class ABC:
def __init__(self, n_clusters, n_employed_bees, n_onlooker_bees, n_iterations):
self.n_clusters = n_clusters
self.n_employed_bees = n_employed_bees
self.n_onlooker_bees = n_onlooker_bees
self.n_iterations = n_iterations
self.dimension = None
self.lower_bound = None
self.upper_bound = None
self.food_sources = None
self.trial_counts = None
self.fitness_values = None
self.best_source = None
self.best_fitness = None
def fit(self, X):
self.dimension = X.shape[1]
self.lower_bound = np.min(X, axis=0)
self.upper_bound = np.max(X, axis=0)
self.food_sources = np.random.uniform(self.lower_bound, self.upper_bound, size=(self.n_employed_bees, self.dimension))
self.trial_counts = np.zeros(self.n_employed_bees)
self.fitness_values = np.zeros(self.n_employed_bees)
self.evaluate(X)
for i in range(self.n_iterations):
self.send_employed_bees()
self.send_onlooker_bees(X)
self.select_best_source()
self.send_scout_bees(X)
def evaluate(self, X):
kmeans = KMeans(n_clusters=self.n_clusters, init=self.food_sources, n_init=1).fit(X)
self.fitness_values = kmeans.inertia_
def send_employed_bees(self):
for i in range(self.n_employed_bees):
j = np.random.choice([x for x in range(self.n_employed_bees) if x != i])
phi = np.random.uniform(-1, 1, size=self.dimension)
new_food_source = self.food_sources[i] + phi * (self.food_sources[i] - self.food_sources[j])
new_fitness_value = self.evaluate_new_source(new_food_source)
if new_fitness_value < self.fitness_values[i]:
self.food_sources[i] = new_food_source
self.fitness_values[i] = new_fitness_value
self.trial_counts[i] = 0
else:
self.trial_counts[i] += 1
def evaluate_new_source(self, source):
source = np.clip(source, self.lower_bound, self.upper_bound)
kmeans = KMeans(n_clusters=self.n_clusters, init=source.reshape(1, -1), n_init=1).fit(X)
return kmeans.inertia_
def send_onlooker_bees(self, X):
probabilities = self.fitness_values / np.sum(self.fitness_values)
for i in range(self.n_onlooker_bees):
j = np.random.choice(range(self.n_employed_bees), p=probabilities)
phi = np.random.uniform(-1, 1, size=self.dimension)
new_food_source = self.food_sources[j] + phi * (self.food_sources[j] - self.food_sources[np.random.choice([x for x in range(self.n_employed_bees) if x != j])])
new_fitness_value = self.evaluate_new_source(new_food_source)
if new_fitness_value < self.fitness_values[j]:
self.food_sources[j] = new_food_source
self.fitness_values[j] = new_fitness_value
self.trial_counts[j] = 0
else:
self.trial_counts[j] += 1
def select_best_source(self):
index = np.argmin(self.fitness_values)
if self.best_fitness is None or self.fitness_values[index] < self.best_fitness:
self.best_fitness = self.fitness_values[index]
self.best_source = self.food_sources[index]
def send_scout_bees(self, X):
for i in range(self.n_employed_bees):
if self.trial_counts[i] >= self.n_employed_bees:
self.food_sources[i] = np.random.uniform(self.lower_bound, self.upper_bound, size=self.dimension)
self.trial_counts[i] = 0
self.evaluate(X)
def predict(self, X):
kmeans = KMeans(n_clusters=self.n_clusters, init=self.best_source.reshape(1, -1), n_init=1).fit(X)
return kmeans.labels_
if __name__ == '__main__':
X, y = make_blobs(n_samples=1000, centers=3, n_features=2, random_state=42)
abc = ABC(n_clusters=3, n_employed_bees=10, n_onlooker_bees=10, n_iterations=100)
abc.fit(X)
print(abc.predict(X))
```
该示例使用sklearn的make_blobs函数生成了一个随机数据集,然后使用聚类人工蜂群算法对其进行聚类。算法的核心循环中包含了四个步骤:(1) 送出雇用蜂,(2) 送出观察蜂,(3) 选择最佳食物源,(4) 送出侦查蜂。在每个步骤中,都会更新食物源的位置和适应度值,并记录试验次数。算法最终输出数据点的聚类标签。
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