编写pytorch代码,定义LSTMAttention模型,定义个FA_CPSO优化算法,读取特征训练集X_train和标签训练集y_train,训练模型,利用萤火虫随机扰动的参数和混沌映射系数调整粒子群参数,调用优化算法去优化模型的损失函数,将最优的参数设置给模型,然后在读取特征测试集X_test和标签测试集y_test,再测试集上测试模型,继续优化模型,将优化后的参数设置给模型,并输出测试损失,绘制测试集的预测值和实际值,计算测试集的均方根误差,加载预测集,绘制预测集的实际值和预测值
时间: 2024-04-02 16:35:56 浏览: 94
好的,我明白了。下面是代码实现:
```python
import torch
import torch.nn as nn
import numpy as np
import random
# 定义LSTMAttention模型
class LSTMAttention(nn.Module):
def __init__(self, input_size, hidden_size, output_size):
super(LSTMAttention, self).__init__()
self.hidden_size = hidden_size
self.lstm = nn.LSTM(input_size, hidden_size, batch_first=True)
self.linear = nn.Linear(hidden_size, output_size)
self.softmax = nn.Softmax(dim=1)
def forward(self, inputs):
output, _ = self.lstm(inputs)
attention_weights = self.softmax(self.linear(output))
context_vector = torch.sum(attention_weights * output, dim=1)
output = self.linear(context_vector)
return output
# 定义FA_CPSO优化算法
class Particle:
def __init__(self, position, velocity, fitness, personal_best_position, personal_best_fitness):
self.position = position
self.velocity = velocity
self.fitness = fitness
self.personal_best_position = personal_best_position
self.personal_best_fitness = personal_best_fitness
class Swarm:
def __init__(self, num_particles, num_params, X_train, y_train, X_test, y_test):
self.num_particles = num_particles
self.num_params = num_params
self.X_train = X_train
self.y_train = y_train
self.X_test = X_test
self.y_test = y_test
self.particles = []
self.global_best_position = None
self.global_best_fitness = float('inf')
self.w = 0.729
self.c1 = 1.49445
self.c2 = 1.49445
# 初始化粒子群
for i in range(self.num_particles):
position = np.random.uniform(low=-1.0, high=1.0, size=self.num_params)
velocity = np.zeros(self.num_params)
fitness = self.evaluate(position)
personal_best_position = np.copy(position)
personal_best_fitness = fitness
particle = Particle(position, velocity, fitness, personal_best_position, personal_best_fitness)
self.particles.append(particle)
# 计算模型的损失函数
def evaluate(self, position):
model = LSTMAttention(input_size=1, hidden_size=32, output_size=1)
optimizer = torch.optim.Adam(model.parameters(), lr=0.01)
criterion = nn.MSELoss()
num_epochs = 100
# 调整模型参数
for epoch in range(num_epochs):
inputs = torch.from_numpy(self.X_train).unsqueeze(2).float()
labels = torch.from_numpy(self.y_train).float()
optimizer.zero_grad()
outputs = model(inputs)
loss = criterion(outputs, labels)
loss.backward()
optimizer.step()
# 使用模型预测测试集并计算损失函数
inputs = torch.from_numpy(self.X_test).unsqueeze(2).float()
labels = torch.from_numpy(self.y_test).float()
outputs = model(inputs)
test_loss = criterion(outputs, labels)
return test_loss.item()
# 更新粒子群的位置和速度
def update(self):
for particle in self.particles:
r1 = random.random()
r2 = random.random()
# 更新速度
particle.velocity = self.w * particle.velocity \
+ self.c1 * r1 * (particle.personal_best_position - particle.position) \
+ self.c2 * r2 * (self.global_best_position - particle.position)
# 更新位置
particle.position = particle.position + particle.velocity
# 更新个体最优解
fitness = self.evaluate(particle.position)
if fitness < particle.personal_best_fitness:
particle.personal_best_position = np.copy(particle.position)
particle.personal_best_fitness = fitness
# 更新全局最优解
if fitness < self.global_best_fitness:
self.global_best_position = np.copy(particle.position)
self.global_best_fitness = fitness
# 扰动粒子群的参数
def perturb(self, chaos_map):
for particle in self.particles:
for i in range(len(particle.position)):
particle.position[i] = particle.position[i] + chaos_map[i]
# 运行粒子群优化算法
def run(self, num_iterations):
chaos_map = self.generate_chaos_map()
for i in range(num_iterations):
self.update()
self.perturb(chaos_map)
print('Iteration:', i, ', Best fitness:', self.global_best_fitness)
# 产生萤火虫随机扰动的参数
def generate_chaos_map(self):
x = 0.1
y = 0.1
z = 0.1
a = 10
b = 28
c = 8/3
chaos_map = []
for i in range(self.num_params):
x_new = y - x
y_new = x * (b - z) - y
z_new = x * y - c * z
x = x_new
y = y_new
z = z_new
chaos_map.append(a * abs(z))
return chaos_map
# 读取特征训练集X_train和标签训练集y_train
X_train = np.load('X_train.npy')
y_train = np.load('y_train.npy')
# 读取特征测试集X_test和标签测试集y_test
X_test = np.load('X_test.npy')
y_test = np.load('y_test.npy')
# 定义粒子群
swarm = Swarm(num_particles=10, num_params=32, X_train=X_train, y_train=y_train, X_test=X_test, y_test=y_test)
# 运行粒子群优化算法
swarm.run(num_iterations=50)
# 将最优的参数设置给模型
model = LSTMAttention(input_size=1, hidden_size=32, output_size=1)
model.load_state_dict(torch.load('best_model.pt'))
# 在测试集上测试模型
inputs = torch.from_numpy(X_test).unsqueeze(2).float()
labels = torch.from_numpy(y_test).float()
outputs = model(inputs)
test_loss = nn.MSELoss()(outputs, labels)
print('Test loss:', test_loss.item())
# 绘制测试集的预测值和实际值
import matplotlib.pyplot as plt
plt.plot(outputs.detach().numpy(), label='Predicted')
plt.plot(labels.numpy(), label='Actual')
plt.legend()
plt.show()
# 计算测试集的均方根误差
from sklearn.metrics import mean_squared_error
rmse = mean_squared_error(labels.numpy(), outputs.detach().numpy(), squared=False)
print('Test RMSE:', rmse)
# 加载预测集
X_pred = np.load('X_pred.npy')
# 预测并绘制预测集的实际值和预测值
inputs = torch.from_numpy(X_pred).unsqueeze(2).float()
outputs = model(inputs)
plt.plot(outputs.detach().numpy(), label='Predicted')
plt.legend()
plt.show()
```
需要注意的是,这只是一种实现方式,具体的实现方法可能因为数据的不同而有所不同。因此,您需要根据自己的数据和需求进行适当的修改。
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