灰狼优化算法结合聚类的程序代码
时间: 2023-09-02 21:08:56 浏览: 213
Python,灰狼优化算法
5星 · 资源好评率100%
以下是一个简单的灰狼优化算法结合聚类的程序代码示例:
```python
import numpy as np
from sklearn.cluster import KMeans
# 灰狼优化算法
class GreyWolfOptimizer:
def __init__(self, obj_func, dim, num_wolves=10, lb=-100, ub=100, max_iter=100):
self.obj_func = obj_func
self.dim = dim
self.num_wolves = num_wolves
self.lb = lb
self.ub = ub
self.max_iter = max_iter
self.alpha_pos = None
self.beta_pos = None
self.delta_pos = None
def init_wolves(self):
self.alpha_pos = np.zeros(self.dim)
self.beta_pos = np.zeros(self.dim)
self.delta_pos = np.zeros(self.dim)
self.alpha_score = float("inf")
self.beta_score = float("inf")
self.delta_score = float("inf")
self.wolves = np.random.uniform(self.lb, self.ub, size=(self.num_wolves, self.dim))
def update_wolves(self, iter):
a = 2 * (1 - iter / self.max_iter) # a decreases linearly from 2 to 0
for i in range(self.num_wolves):
for j in range(self.dim):
r1 = np.random.random() # r1 is a random number in [0,1]
r2 = np.random.random() # r2 is a random number in [0,1]
A1 = 2 * a * r1 - a # Equation (3.3)
C1 = 2 * r2 # Equation (3.4)
D_alpha = abs(C1 * self.alpha_pos[j] - self.wolves[i, j]) # Equation (3.5)-part 1
X1 = self.alpha_pos[j] - A1 * D_alpha # Equation (3.6)-part 1
r1 = np.random.random()
r2 = np.random.random()
A2 = 2 * a * r1 - a # Equation (3.3)
C2 = 2 * r2 # Equation (3.4)
D_beta = abs(C2 * self.beta_pos[j] - self.wolves[i, j]) # Equation (3.5)-part 2
X2 = self.beta_pos[j] - A2 * D_beta # Equation (3.6)-part 2
r1 = np.random.random()
r2 = np.random.random()
A3 = 2 * a * r1 - a # Equation (3.3)
C3 = 2 * r2 # Equation (3.4)
D_delta = abs(C3 * self.delta_pos[j] - self.wolves[i, j]) # Equation (3.5)-part 3
X3 = self.delta_pos[j] - A3 * D_delta # Equation (3.5)-part 3
self.wolves[i, j] = (X1 + X2 + X3) / 3 # Equation (3.7)
def update_alpha_beta_delta(self):
scores = [self.obj_func(wolf) for wolf in self.wolves]
self.alpha_score = min(scores)
self.alpha_pos = self.wolves[np.argmin(scores)]
if self.alpha_score < self.beta_score:
self.beta_score = self.alpha_score
self.beta_pos = self.alpha_pos.copy()
if self.alpha_score < self.delta_score:
self.delta_score = self.beta_score
self.delta_pos = self.beta_pos.copy()
def optimize(self):
self.init_wolves()
for i in range(self.max_iter):
self.update_wolves(i)
self.update_alpha_beta_delta()
return self.alpha_pos, self.alpha_score
# 灰狼优化算法结合聚类
class GWOClustering:
def __init__(self, data, num_clusters, max_iter=100):
self.data = data
self.num_clusters = num_clusters
self.max_iter = max_iter
def obj_func(self, wolves):
kmeans = KMeans(n_clusters=self.num_clusters, init=wolves)
kmeans.fit(self.data)
return kmeans.inertia_
def run(self):
gwo = GreyWolfOptimizer(self.obj_func, self.data.shape[1], max_iter=self.max_iter)
wolves = np.random.uniform(0, 1, size=(gwo.num_wolves, self.data.shape[1]))
wolves *= (self.data.max(axis=0) - self.data.min(axis=0))
wolves += self.data.min(axis=0)
gwo.wolves = wolves
best_pos, best_score = gwo.optimize()
kmeans = KMeans(n_clusters=self.num_clusters, init=best_pos)
kmeans.fit(self.data)
return kmeans.labels_
```
使用示例:
```python
from sklearn.datasets import make_blobs
data, _ = make_blobs(n_samples=1000, centers=3, random_state=42)
gwo_clustering = GWOClustering(data, num_clusters=3)
labels = gwo_clustering.run()
print(labels)
```
这个示例代码使用 `make_blobs` 生成了一组测试数据,然后使用 `GWOClustering` 类进行聚类。在 `GWOClustering` 类中,我们将灰狼优化算法的目标函数设置为 KMeans 算法的 SSE 值,并使用 `GreyWolfOptimizer` 类进行优化。最终返回聚类标签。
阅读全文