mean_p = predict.mean(axis=0)是什么意思
时间: 2024-05-30 20:15:00 浏览: 20
这个代码行是在对预测结果进行操作。"predict" 是一个数组,可能是由模型预测得到的,"mean(axis=0)"则是对这个数组进行操作求平均值,其中的 "axis=0" 表示按照第一维 (即第一个轴,这通常是一个样本) 操作。这行代码的意思是取预测结果的每一个特征的平均值,返回一个包含每一个特征平均值的一维数组。
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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:
```python
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))
```
def mcp_loss(f_new): """ 计算单调性约束损失函数在所有样本和时刻上的平均值 """ batch_size = 64 num_timesteps = 6 num_features = 15 delta_p = tf.random.uniform(shape=(batch_size, num_timesteps, num_features), minval=0, maxval=1) p = inputs[:, :, -15:] p_new = p + delta_p newinputs = np.concatenate([train_ds[:, :, 0], p_new], axis=-1) f = ssmodel.predict(train_ds) f_new = ssmodel.predict(newinputs) # 预测 f_new delta_f = f - f_new relu = tf.nn.relu(delta_f) return tf.reduce_mean(tf.square(relu)) def combined_loss(y_true, y_pred): """ 组合MSE损失函数和单调性约束损失函数的新损失函数 """ def loss(y_true,y_pred): return alpha* mean_squared_error(y_true, y_pred) + (1-alpha) * mcp_loss() return loss将这段代码修改为keras的自定义损失函数的正确形式
可以将上述代码修改为 Keras 的自定义损失函数的正确形式,如下所示:
```python
import tensorflow as tf
from tensorflow.keras.losses import mean_squared_error
def mcp_loss(y_true, y_pred):
"""
计算单调性约束损失函数在所有样本和时刻上的平均值
"""
delta_p = tf.random.uniform(shape=(batch_size, num_timesteps, num_features), minval=0, maxval=1)
p = y_true[:, :, -15:]
p_new = p + delta_p
newinputs = tf.concat([y_true[:, :, 0], p_new], axis=-1)
f = ssmodel.predict(y_true)
f_new = ssmodel.predict(newinputs) # 预测 f_new
delta_f = f - f_new
relu = tf.nn.relu(delta_f)
return tf.reduce_mean(tf.square(relu))
def combined_loss(y_true, y_pred):
"""
组合MSE损失函数和单调性约束损失函数的新损失函数
"""
alpha = 0.5 # 可以根据需要进行调整
mse_loss = mean_squared_error(y_true, y_pred)
mcp_loss_val = mcp_loss(y_true, y_pred)
return alpha * mse_loss + (1 - alpha) * mcp_loss_val
```
在上述代码中,`mcp_loss` 函数和 `combined_loss` 函数都采用了 Keras 的标准输入格式:`y_true` 和 `y_pred`,分别表示真实值和预测值。在 `mcp_loss` 函数中,我们使用 `tf.random.uniform` 函数生成一个与 `y_true` 相同形状的随机张量 `delta_p`,并使用它来计算新的输入 `newinputs` 和相应的预测值 `f_new`。然后,我们计算 `delta_f` 和 ReLU 函数,并将其平方并取平均值作为单调性约束损失函数的值。在 `combined_loss` 函数中,我们将 MSE 损失函数和单调性约束损失函数的值组合在一起,并返回它们的加权平均值作为最终的损失函数值。
请注意,上述代码可能需要根据您的具体情况进行适当修改,例如调整 `alpha` 或修改输入和输出的形状。