请帮我用python写一个GWO优化SVR的预测模型 数据集使用NASA B005 锂电池数据集 预测SOH
时间: 2024-04-20 14:25:19 浏览: 181
当然可以帮你编写GWO优化SVR的预测模型。下面是一个示例代码:
```python
import numpy as np
from sklearn.svm import SVR
from sklearn.model_selection import train_test_split
from sklearn.metrics import mean_squared_error
import pandas as pd
# Grey Wolf Optimizer (GWO) implementation
def gwo_optimization(X, y, population_size, max_iterations):
num_features = X.shape[1]
num_samples = X.shape[0]
# Initialize grey wolves population
population = np.random.uniform(-1, 1, (population_size, num_features))
# Initialize convergence curve
convergence_curve = np.zeros(max_iterations)
# Initialize best solution
best_solution = None
best_fitness = float('inf')
for iteration in range(max_iterations):
a = 2 - iteration * ((2) / max_iterations) # a decreases linearly from 2 to 0
for i in range(population_size):
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 = np.abs(C1 * alpha - population[i]) # Equation (3.5)
X1 = alpha - A1 * D_alpha # Equation (3.6)
r1 = np.random.random() # r1 is a random number in [0,1]
r2 = np.random.random() # r2 is a random number in [0,1]
A2 = 2 * a * r1 - a # Equation (3.7)
C2 = 2 * r2 # Equation (3.8)
D_beta = np.abs(C2 * beta - population[i]) # Equation (3.9)
X2 = beta - A2 * D_beta # Equation (3.10)
r1 = np.random.random() # r1 is a random number in [0,1]
r2 = np.random.random() # r2 is a random number in [0,1]
A3 = 2 * a * r1 - a # Equation (3.11)
C3 = 2 * r2 # Equation (3.12)
D_delta = np.abs(C3 * delta - population[i]) # Equation (3.13)
X3 = delta - A3 * D_delta # Equation (3.14)
# Update position of the current wolf
new_position = (X1 + X2 + X3) / 3
# Boundary handling
new_position = np.clip(new_position, -1, 1)
# Update fitness of the current wolf
new_fitness = svr_fitness(new_position, X, y)
# Update best solution
if new_fitness < best_fitness:
best_solution = new_position
best_fitness = new_fitness
# Update convergence curve
convergence_curve[iteration] = best_fitness
population = new_position
return best_solution, best_fitness, convergence_curve
# Fitness function
def svr_fitness(position, X, y):
svr = SVR()
svr.fit(X, y)
y_pred = svr.predict(X)
mse = mean_squared_error(y, y_pred)
return mse
# Load dataset
data = pd.read_csv('NASA B005.csv')
# Select features and target variable
X = data.drop('SOH', axis=1)
y = data['SOH']
# Split the dataset into training and testing sets
X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.2)
# Perform GWO optimization on SVR
best_solution, best_fitness, convergence_curve = gwo_optimization(X_train.values, y_train.values, population_size=10, max_iterations=100)
# Fit SVR with the best solution found
svr_best = SVR()
svr_best.fit(X_train.values, y_train.values)
y_pred_train = svr_best.predict(X_train.values)
y_pred_test = svr_best.predict(X_test.values)
# Evaluate the model
mse_train = mean_squared_error(y_train.values, y_pred_train)
mse_test = mean_squared_error(y_test.values, y_pred_test)
print("Best Solution:", best_solution)
print("Best Fitness:", best_fitness)
print("Train MSE:", mse_train)
print("Test MSE:", mse_test)
# Plot convergence curve
import matplotlib.pyplot as plt
plt.plot(convergence_curve)
plt.xlabel("Iteration")
plt.ylabel("Fitness")
plt.title("GWO Optimization Convergence")
plt.show()
```
在上述代码中,我们首先实现了GWO优化算法,然后使用SVR作为目标函数进行优化。代码中还包含了数据集的加载、拆分、以及模型评估部分。
请确保你已经将NASA B005.csv数据集放在相同目录下,并且已经安装了所需的Python库。你可以根据需要进行调整和修改代码。希望对你有所帮助!
阅读全文