python读取txt文件送入GA优化的LSTM训练和预测,并输出图像代码
时间: 2024-05-05 20:20:24 浏览: 10
抱歉,我可以回答关于Python读取txt文件送入GA优化的LSTM训练和预测,并输出图像的问题。以下是代码示例:
首先需要导入必要的库:
```python
import numpy as np
import pandas as pd
import matplotlib.pyplot as plt
from keras.models import Sequential
from keras.layers import Dense
from keras.layers import LSTM
from keras.callbacks import EarlyStopping
from sklearn.preprocessing import MinMaxScaler
```
然后读取txt文件,我们假设文件名为“data.txt”,数据以逗号分隔,每行为一个时间序列数据:
```python
data = pd.read_csv('data.txt',sep=',',header=None)
```
接下来进行数据预处理,包括归一化和划分训练集和测试集:
```python
scaler = MinMaxScaler(feature_range=(0, 1))
data_scaled = scaler.fit_transform(data)
train_size = int(len(data_scaled) * 0.7)
test_size = len(data_scaled) - train_size
train, test = data_scaled[0:train_size,:], data_scaled[train_size:len(data_scaled),:]
```
我们使用遗传算法(GA)进行LSTM参数优化,定义LSTM模型:
```python
def create_model(num_hidden_units,num_lstm_layers,batch_size,time_steps,features):
model = Sequential()
model.add(LSTM(num_hidden_units, input_shape=(time_steps, features)))
for i in range(num_lstm_layers - 1):
model.add(LSTM(num_hidden_units, return_sequences=True))
model.add(Dense(features))
model.compile(loss='mse', optimizer='adam')
return model
```
定义GA目标函数:
```python
def lstm_score(params):
num_hidden_units, num_lstm_layers, batch_size, time_steps = params
model = create_model(num_hidden_units,num_lstm_layers,batch_size,time_steps,features)
model.fit(trainX, trainY, epochs=100, batch_size=batch_size, verbose=0, callbacks=[early_stopping],shuffle=False)
trainScore = model.evaluate(trainX, trainY, verbose=0)
testScore = model.evaluate(testX, testY, verbose=0)
return testScore
```
执行GA优化,得到最优参数:
```python
from pyeasyga import pyeasyga
features = 1
num_generations = 10
population_size = 30
mutation_probability = 0.1
ga = pyeasyga.GeneticAlgorithm(param_bounds=[
(20, 100), # num_hidden_units
(1, 5), # num_lstm_layers
(10, 50), # batch_size
(10, 30) # time_steps
])
ga.population_size = population_size
ga.mutation_probability = mutation_probability
ga.fitness_function = lstm_score
ga.create_individual = lambda: [
np.random.randint(20, 101), # num_hidden_units
np.random.randint(1, 6), # num_lstm_layers
np.random.randint(10, 51), # batch_size
np.random.randint(10, 31) # time_steps
]
ga.evolve(num_generations=10)
best_params = ga.best_individual()[0]
```
使用得到的最优参数,训练模型并预测结果:
```python
num_hidden_units, num_lstm_layers, batch_size, time_steps = best_params
model = create_model(num_hidden_units,num_lstm_layers,batch_size,time_steps,features)
early_stopping = EarlyStopping(monitor='loss', patience=5)
trainX, trainY = create_dataset(train, time_steps)
testX, testY = create_dataset(test, time_steps)
model.fit(trainX, trainY, epochs=100, batch_size=batch_size, verbose=0, callbacks=[early_stopping],shuffle=False)
trainPredict = model.predict(trainX)
testPredict = model.predict(testX)
trainPredict = scaler.inverse_transform(trainPredict)
trainY = scaler.inverse_transform([trainY])
testPredict = scaler.inverse_transform(testPredict)
testY = scaler.inverse_transform([testY])
trainPredictPlot = np.empty_like(data_scaled)
trainPredictPlot[:, :] = np.nan
trainPredictPlot[time_steps:len(trainPredict)+time_steps, :] = trainPredict
testPredictPlot = np.empty_like(data_scaled)
testPredictPlot[:, :] = np.nan
testPredictPlot[len(trainPredict)+(time_steps*2):len(data_scaled), :] = testPredict
plt.plot(scaler.inverse_transform(data_scaled))
plt.plot(trainPredictPlot)
plt.plot(testPredictPlot)
plt.show()
```
最后,我们可以得到训练结果和预测结果的图像。