data_predict = train_predict.data.numpy() dataY_plot = dataY.data.numpy()甚么意思？

这两行代码是将 PyTorch Tensor 对象转换为 NumPy 数组。具体来说，train_predict 和 dataY 都是 PyTorch 的 Tensor 对象，调用 .data 属性可以获取其底层的 NumPy 数组。然后将这些 NumPy 数组分别赋值给 data_predict 和 dataY_plot 变量，用于后续的数据可视化或其他操作。

相关问题

下面的这段python代码，哪里有错误，修改一下：import numpy as np import matplotlib.pyplot as plt import pandas as pd import torch import torch.nn as nn from torch.autograd import Variable from sklearn.preprocessing import MinMaxScaler training_set = pd.read_csv('CX2-36_1971.csv') training_set = training_set.iloc[:, 1:2].values def sliding_windows(data, seq_length): x = [] y = [] for i in range(len(data) - seq_length): _x = data[i:(i + seq_length)] _y = data[i + seq_length] x.append(_x) y.append(_y) return np.array(x), np.array(y) sc = MinMaxScaler() training_data = sc.fit_transform(training_set) seq_length = 1 x, y = sliding_windows(training_data, seq_length) train_size = int(len(y) * 0.8) test_size = len(y) - train_size dataX = Variable(torch.Tensor(np.array(x))) dataY = Variable(torch.Tensor(np.array(y))) trainX = Variable(torch.Tensor(np.array(x[1:train_size]))) trainY = Variable(torch.Tensor(np.array(y[1:train_size]))) testX = Variable(torch.Tensor(np.array(x[train_size:len(x)]))) testY = Variable(torch.Tensor(np.array(y[train_size:len(y)]))) class LSTM(nn.Module): def __init__(self, num_classes, input_size, hidden_size, num_layers): super(LSTM, self).__init__() self.num_classes = num_classes self.num_layers = num_layers self.input_size = input_size self.hidden_size = hidden_size self.seq_length = seq_length self.lstm = nn.LSTM(input_size=input_size, hidden_size=hidden_size, num_layers=num_layers, batch_first=True) self.fc = nn.Linear(hidden_size, num_classes) def forward(self, x): h_0 = Variable(torch.zeros( self.num_layers, x.size(0), self.hidden_size)) c_0 = Variable(torch.zeros( self.num_layers, x.size(0), self.hidden_size)) # Propagate input through LSTM ula, (h_out, _) = self.lstm(x, (h_0, c_0)) h_out = h_out.view(-1, self.hidden_size) out = self.fc(h_out) return out num_epochs = 2000 learning_rate = 0.001 input_size = 1 hidden_size = 2 num_layers = 1 num_classes = 1 lstm = LSTM(num_classes, input_size, hidden_size, num_layers) criterion = torch.nn.MSELoss() # mean-squared error for regression optimizer = torch.optim.Adam(lstm.parameters(), lr=learning_rate) # optimizer = torch.optim.SGD(lstm.parameters(), lr=learning_rate) runn = 10 Y_predict = np.zeros((runn, len(dataY))) # Train the model for i in range(runn): print('Run: ' + str(i + 1)) for epoch in range(num_epochs): outputs = lstm(trainX) optimizer.zero_grad() # obtain the loss function loss = criterion(outputs, trainY) loss.backward() optimizer.step() if epoch % 100 == 0: print("Epoch: %d, loss: %1.5f" % (epoch, loss.item())) lstm.eval() train_predict = lstm(dataX) data_predict = train_predict.data.numpy() dataY_plot = dataY.data.numpy() data_predict = sc.inverse_transform(data_predict) dataY_plot = sc.inverse_transform(dataY_plot) Y_predict[i,:] = np.transpose(np.array(data_predict)) Y_Predict = np.mean(np.array(Y_predict)) Y_Predict_T = np.transpose(np.array(Y_Predict))

在这段代码中，可能存在以下错误：

1. 缺少必要的库或模块。

2. training_set 的文件路径是否正确。

3. training_set 的数据处理是否正确。

4. LSTM 模型的定义是否正确。

5. 训练和预测的代码是否正确。

下面是修改后的代码：

import numpy as np
import matplotlib.pyplot as plt
import pandas as pd
import torch
import torch.nn as nn
from torch.autograd import Variable
from sklearn.preprocessing import MinMaxScaler

# 读取数据
training_set = pd.read_csv('CX2-36_1971.csv')
training_set = training_set.iloc[:, 1:2].values

# 定义数据处理函数
def sliding_windows(data, seq_length):
    x = []
    y = []
    
    for i in range(len(data) - seq_length):
        _x = data[i:(i + seq_length)]
        _y = data[i + seq_length]
        x.append(_x)
        y.append(_y)
    
    return np.array(x), np.array(y)

# 对数据进行归一化处理
sc = MinMaxScaler()
training_data = sc.fit_transform(training_set)

# 定义窗口长度
seq_length = 1

# 对数据进行窗口划分
x, y = sliding_windows(training_data, seq_length)

# 划分训练集和测试集
train_size = int(len(y) * 0.8)
test_size = len(y) - train_size

dataX = Variable(torch.Tensor(np.array(x)))
dataY = Variable(torch.Tensor(np.array(y)))

trainX = Variable(torch.Tensor(np.array(x[1:train_size])))
trainY = Variable(torch.Tensor(np.array(y[1:train_size])))

testX = Variable(torch.Tensor(np.array(x[train_size:len(x)])))
testY = Variable(torch.Tensor(np.array(y[train_size:len(y)])))

# 定义 LSTM 模型
class LSTM(nn.Module):
    def __init__(self, num_classes, input_size, hidden_size, num_layers):
        super(LSTM, self).__init__()
        
        self.num_classes = num_classes
        self.num_layers = num_layers
        self.input_size = input_size
        self.hidden_size = hidden_size
        self.seq_length = seq_length
        
        self.lstm = nn.LSTM(input_size=input_size, hidden_size=hidden_size,
                            num_layers=num_layers, batch_first=True)
        
        self.fc = nn.Linear(hidden_size, num_classes)
    
    def forward(self, x):
        h_0 = Variable(torch.zeros(
            self.num_layers, x.size(0), self.hidden_size))
        
        c_0 = Variable(torch.zeros(
            self.num_layers, x.size(0), self.hidden_size))
        
        # Propagate input through LSTM
        ula, (h_out, _) = self.lstm(x, (h_0, c_0))
        
        h_out = h_out.view(-1, self.hidden_size)
        
        out = self.fc(h_out)
        
        return out

# 定义训练参数
num_epochs = 2000
learning_rate = 0.001
input_size = 1
hidden_size = 2
num_layers = 1
num_classes = 1

# 实例化 LSTM 模型
lstm = LSTM(num_classes, input_size, hidden_size, num_layers)

# 定义损失函数和优化器
criterion = torch.nn.MSELoss()
optimizer = torch.optim.Adam(lstm.parameters(), lr=learning_rate)

# 训练模型
runn = 10
Y_predict = np.zeros((runn, len(dataY)))

for i in range(runn):
    print('Run: ' + str(i + 1))
    for epoch in range(num_epochs):
        outputs = lstm(trainX)
        optimizer.zero_grad()
        loss = criterion(outputs, trainY)
        loss.backward()
        optimizer.step()
        
        if epoch % 100 == 0:
            print("Epoch: %d, loss: %1.5f" % (epoch, loss.item()))
    
    lstm.eval()
    train_predict = lstm(dataX)
    data_predict = train_predict.data.numpy()
    dataY_plot = dataY.data.numpy()
    
    # 对结果进行反归一化
    data_predict = sc.inverse_transform(data_predict)
    dataY_plot = sc.inverse_transform(dataY_plot)
    
    Y_predict[i,:] = np.transpose(np.array(data_predict))

Y_Predict = np.mean(Y_predict, axis=0)
Y_Predict_T = np.transpose(np.array(Y_Predict))

import pandas as pd import numpy as np import matplotlib.pyplot as plt import tensorflow as tf from tensorflow.keras.models import Sequential from tensorflow.keras.layers import LSTM, Dense data = pd.read_csv('车辆：274序：4结果数据.csv') x = data[['车头间距', '原车道前车速度']].values y = data['本车速度'].values train_size = int(len(x) * 0.7) test_size = len(x) - train_size x_train, x_test = x[0:train_size,:], x[train_size:len(x),:] y_train, y_test = y[0:train_size], y[train_size:len(y)] from sklearn.preprocessing import MinMaxScaler scaler = MinMaxScaler(feature_range=(0, 1)) x_train = scaler.fit_transform(x_train) x_test = scaler.transform(x_test) model = Sequential() model.add(LSTM(50, input_shape=(2, 1))) model.add(Dense(1)) model.compile(loss='mean_squared_error', optimizer='adam') history = model.fit(x_train.reshape(-1, 2, 1), y_train, epochs=100, batch_size=32, validation_data=(x_test.reshape(-1, 2, 1), y_test)) plt.plot(history.history['loss']) plt.plot(history.history['val_loss']) plt.title('Model loss') plt.ylabel('Loss') plt.xlabel('Epoch') plt.legend(['Train', 'Test'], loc='upper right') plt.show() train_predict = model.predict(x_train.reshape(-1, 2, 1)) test_predict = model.predict(x_test.reshape(-1, 2, 1)) train_predict = scaler.inverse_transform(train_predict) train_predict = train_predict.reshape(-1) # 将结果变为一维数组 y_train = scaler.inverse_transform(y_train.reshape(-1, 1)).reshape(-1) # 将结果变为一维数组 test_predict = scaler.inverse_transform(test_predict) y_test = scaler.inverse_transform([y_test]) plt.plot(y_train[0], label='train') plt.plot(train_predict[:,0], label='train predict') plt.plot(y_test[0], label='test') plt.plot(test_predict[:,0], label='test predict') plt.legend() plt.show()报错Traceback (most recent call last): File "C:\Users\马斌\Desktop\NGSIM_data_processing\80s\lstmtest.py", line 42, in <module> train_predict = scaler.inverse_transform(train_predict) File "D:\python\python3.9.5\pythonProject\venv\lib\site-packages\sklearn\preprocessing\_data.py", line 541, in inverse_transform X -= self.min_ ValueError: non-broadcastable output operand with shape (611,1) doesn't match the broadcast shape (611,2)

这个错误发生在将归一化后的预测结果进行逆归一化时。根据错误提示，训练集的预测结果和真实值的形状为 (611,)，而测试集的预测结果和真实值的形状为 (1, 611)。这是因为在进行逆归一化时，要求预测结果和真实值的形状必须一致，即都为一维数组。

你可以将 y_test 的形状改为 (611,)，方法是将 y_test 的数据类型从二维数组转换为一维数组，就像对 y_train 做的那样。修改后的代码如下：

import pandas as pd 
import numpy as np 
import matplotlib.pyplot as plt 
import tensorflow as tf 
from tensorflow.keras.models import Sequential 
from tensorflow.keras.layers import LSTM, Dense  

data = pd.read_csv('车辆：274序：4结果数据.csv') 

x = data[['车头间距', '原车道前车速度']].values 
y = data['本车速度'].values 

train_size = int(len(x) * 0.7) 
test_size = len(x) - train_size 

x_train, x_test = x[0:train_size,:], x[train_size:len(x),:] 
y_train, y_test = y[0:train_size], y[train_size:len(y)]  

from sklearn.preprocessing import MinMaxScaler 

scaler = MinMaxScaler(feature_range=(0, 1)) 
x_train = scaler.fit_transform(x_train) 
x_test = scaler.transform(x_test)  

model = Sequential() 
model.add(LSTM(50, input_shape=(2, 1))) 
model.add(Dense(1)) 
model.compile(loss='mean_squared_error', optimizer='adam')  

history = model.fit(x_train.reshape(-1, 2, 1), y_train, epochs=100, batch_size=32, validation_data=(x_test.reshape(-1, 2, 1), y_test))  

plt.plot(history.history['loss']) 
plt.plot(history.history['val_loss']) 
plt.title('Model loss') 
plt.ylabel('Loss') 
plt.xlabel('Epoch') 
plt.legend(['Train', 'Test'], loc='upper right') 
plt.show()  

train_predict = model.predict(x_train.reshape(-1, 2, 1)) 
test_predict = model.predict(x_test.reshape(-1, 2, 1))  

train_predict = scaler.inverse_transform(train_predict) 
train_predict = train_predict.reshape(-1) # 将结果变为一维数组 
y_train = scaler.inverse_transform(y_train.reshape(-1, 1)).reshape(-1) # 将结果变为一维数组 

test_predict = scaler.inverse_transform(test_predict) 
y_test = scaler.inverse_transform(y_test.reshape(-1, 1)).reshape(-1) # 将结果变为一维数组

plt.plot(y_train, label='train') 
plt.plot(train_predict, label='train predict') 
plt.plot(y_test, label='test') 
plt.plot(test_predict, label='test predict') 
plt.legend() 
plt.show()