Python实现多步预测以及误差分析和可视化代码
时间: 2024-02-22 13:56:16 浏览: 179
好的,以下为Python实现多步预测以及误差分析和可视化代码:
首先,我们需要导入相关的库:
```python
import numpy as np
import pandas as pd
import matplotlib.pyplot as plt
from sklearn.preprocessing import MinMaxScaler
from tensorflow.keras.models import Sequential
from tensorflow.keras.layers import Dense, LSTM, Dropout
```
接下来,我们需要准备数据。这里我们以时间序列数据为例,首先读入数据并进行预处理:
```python
# 读入数据
data = pd.read_csv('data.csv', index_col=0, parse_dates=True)
# 将数据按时间排序
data = data.sort_index()
# 将数据归一化到0-1之间
scaler = MinMaxScaler()
data_scaled = scaler.fit_transform(data)
```
然后,我们需要将数据集划分为训练集和测试集:
```python
# 划分训练集和测试集
train_size = int(len(data_scaled) * 0.8)
test_size = len(data_scaled) - train_size
train_data = data_scaled[:train_size, :]
test_data = data_scaled[train_size:, :]
```
接下来,我们需要创建训练集和测试集数据集,这里我们以10个时间步长为输入,1个时间步长为输出进行数据集的创建:
```python
# 创建训练集和测试集数据集
def create_dataset(dataset, lookback, lookahead):
X, Y = [], []
for i in range(len(dataset) - lookback - lookahead):
X.append(dataset[i:(i + lookback), :])
Y.append(dataset[(i + lookback):(i + lookback + lookahead), 0])
return np.array(X), np.array(Y)
lookback = 10
lookahead = 1
X_train, Y_train = create_dataset(train_data, lookback, lookahead)
X_test, Y_test = create_dataset(test_data, lookback, lookahead)
```
然后,我们需要构建LSTM模型,并进行训练:
```python
# 构建LSTM模型
model = Sequential()
model.add(LSTM(units=50, return_sequences=True, input_shape=(X_train.shape[1], X_train.shape[2])))
model.add(Dropout(0.2))
model.add(LSTM(units=50, return_sequences=True))
model.add(Dropout(0.2))
model.add(LSTM(units=50, return_sequences=True))
model.add(Dropout(0.2))
model.add(LSTM(units=50))
model.add(Dropout(0.2))
model.add(Dense(units=lookahead))
# 编译模型
model.compile(optimizer='adam', loss='mean_squared_error')
# 训练模型
history = model.fit(X_train, Y_train, epochs=100, batch_size=32, validation_data=(X_test, Y_test), shuffle=False)
```
接下来,我们可以使用训练好的模型进行多步预测:
```python
# 多步预测
def multi_step_predict(model, X_test, lookahead):
predictions = []
for i in range(len(X_test)):
input_data = X_test[i]
for j in range(lookahead):
prediction = model.predict(input_data.reshape(1, lookback, -1))[0][0]
predictions.append(prediction)
input_data = np.concatenate((input_data[1:], prediction.reshape(1, -1)), axis=0)
return np.array(predictions)
predictions = multi_step_predict(model, X_test, lookahead)
```
最后,我们可以进行误差分析和可视化:
```python
# 误差分析
rmse = np.sqrt(np.mean((predictions - Y_test.reshape(-1)) ** 2))
print('RMSE:', rmse)
# 可视化
fig, ax = plt.subplots(figsize=(10, 6))
ax.plot(Y_test, label='True Value')
ax.plot(predictions, label='Predicted Value')
ax.set_xlabel('Time')
ax.set_ylabel('Value')
ax.legend()
plt.show()
```
以上就是Python实现多步预测以及误差分析和可视化的完整代码。
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