test_pred = pred.detach().cpu().numpy().reshape((7, 2)) test_label = test_label_tensor.cpu().numpy().reshape((7, 2))什么意思
时间: 2023-12-04 21:02:42 浏览: 39
这段代码是将PyTorch张量(pred和test_label_tensor)转换为NumPy数组,并且重新调整形状为(7,2)的二维数组。
首先,`detach()`函数是将一个张量从计算图中分离出来,返回一个新的张量,该新张量的requires_grad属性为False,这样可以避免对原始张量进行计算梯度。
接着,`cpu()`函数将张量从GPU转移到CPU上,因为NumPy数组只能在CPU上使用。
最后,`numpy()`函数将张量转换为NumPy数组,`reshape()`函数将数组重新调整为7行2列的二维数组,以便后续处理。
相关问题
plot_size = 730 plt.figure(figsize=(12, 8)) plt.plot(scaler.inverse_transform((model(x_train_tensor).detach().numpy()[: plot_size]).reshape(-1, 1)), "b") plt.plot(scaler.inverse_transform(y_train_tensor.detach().numpy().reshape(-1, 1)[: plot_size]), "r") plt.legend() plt.show() y_test_pred = model(x_test_tensor) plt.figure(figsize=(12, 8)) plt.plot(scaler.inverse_transform(y_test_pred.detach().numpy()[: plot_size]), "b") plt.plot(scaler.inverse_transform(y_test_tensor.detach().numpy().reshape(-1, 1)[: plot_size]), "r") plt.legend() plt.show()这段代码后加上图片保存到文件夹A中,且图片分别以文件名1、文件名2命名
可以在代码中添加如下代码,实现保存图片到文件夹A中,并分别以文件名1、文件名2命名:
```
# 保存训练集预测结果图片
plt.figure(figsize=(12, 8))
plt.plot(scaler.inverse_transform((model(x_train_tensor).detach().numpy()[: plot_size]).reshape(-1, 1)), "b")
plt.plot(scaler.inverse_transform(y_train_tensor.detach().numpy().reshape(-1, 1)[: plot_size]), "r")
plt.legend()
plt.savefig('./A/文件名1.png')
# 保存测试集预测结果图片
y_test_pred = model(x_test_tensor)
plt.figure(figsize=(12, 8))
plt.plot(scaler.inverse_transform(y_test_pred.detach().numpy()[: plot_size]), "b")
plt.plot(scaler.inverse_transform(y_test_tensor.detach().numpy().reshape(-1, 1)[: plot_size]), "r")
plt.legend()
plt.savefig('./A/文件名2.png')
```
其中,`plt.savefig()`函数可以将图片保存到指定路径和文件名下。需要注意的是,如果`A`文件夹不存在,需要先创建该文件夹,可以使用`os.makedirs()`函数来创建。
import numpy import numpy as np import matplotlib.pyplot as plt import math import torch from torch import nn from torch.utils.data import DataLoader, Dataset import os os.environ['KMP_DUPLICATE_LIB_OK']='True' dataset = [] for data in np.arange(0, 3, .01): data = math.sin(data * math.pi) dataset.append(data) dataset = np.array(dataset) dataset = dataset.astype('float32') max_value = np.max(dataset) min_value = np.min(dataset) scalar = max_value - min_value print(scalar) dataset = list(map(lambda x: x / scalar, dataset)) def create_dataset(dataset, look_back=3): dataX, dataY = [], [] for i in range(len(dataset) - look_back): a = dataset[i:(i + look_back)] dataX.append(a) dataY.append(dataset[i + look_back]) return np.array(dataX), np.array(dataY) data_X, data_Y = create_dataset(dataset) train_X, train_Y = data_X[:int(0.8 * len(data_X))], data_Y[:int(0.8 * len(data_Y))] test_X, test_Y = data_Y[int(0.8 * len(data_X)):], data_Y[int(0.8 * len(data_Y)):] train_X = train_X.reshape(-1, 1, 3).astype('float32') train_Y = train_Y.reshape(-1, 1, 3).astype('float32') test_X = test_X.reshape(-1, 1, 3).astype('float32') train_X = torch.from_numpy(train_X) train_Y = torch.from_numpy(train_Y) test_X = torch.from_numpy(test_X) class RNN(nn.Module): def __init__(self, input_size, hidden_size, output_size=1, num_layer=2): super(RNN, self).__init__() self.input_size = input_size self.hidden_size = hidden_size self.output_size = output_size self.num_layer = num_layer self.rnn = nn.RNN(input_size, hidden_size, batch_first=True) self.linear = nn.Linear(hidden_size, output_size) def forward(self, x): out, h = self.rnn(x) out = self.linear(out[0]) return out net = RNN(3, 20) criterion = nn.MSELoss(reduction='mean') optimizer = torch.optim.Adam(net.parameters(), lr=1e-2) train_loss = [] test_loss = [] for e in range(1000): pred = net(train_X) loss = criterion(pred, train_Y) optimizer.zero_grad() # 反向传播 loss.backward() optimizer.step() if (e + 1) % 100 == 0: print('Epoch:{},loss:{:.10f}'.format(e + 1, loss.data.item())) train_loss.append(loss.item()) plt.plot(train_loss, label='train_loss') plt.legend() plt.show()请适当修改代码,并写出预测值和真实值的代码
以下是适当修改后的代码以及预测值和真实值的代码:
```
import numpy as np
import matplotlib.pyplot as plt
import math
import torch
from torch import nn
from torch.utils.data import DataLoader, Dataset
import os
os.environ['KMP_DUPLICATE_LIB_OK']='True'
dataset = []
for data in np.arange(0, 3, .01):
data = math.sin(data * math.pi)
dataset.append(data)
dataset = np.array(dataset)
dataset = dataset.astype('float32')
max_value = np.max(dataset)
min_value = np.min(dataset)
scalar = max_value - min_value
print(scalar)
dataset = list(map(lambda x: x / scalar, dataset))
def create_dataset(dataset, look_back=3):
dataX, dataY = [], []
for i in range(len(dataset) - look_back):
a = dataset[i:(i + look_back)]
dataX.append(a)
dataY.append(dataset[i + look_back])
return np.array(dataX), np.array(dataY)
data_X, data_Y = create_dataset(dataset)
train_X, train_Y = data_X[:int(0.8 * len(data_X))], data_Y[:int(0.8 * len(data_Y))]
test_X, test_Y = data_Y[int(0.8 * len(data_X)):], data_Y[int(0.8 * len(data_Y)):]
train_X = train_X.reshape(-1, 1, 3).astype('float32')
train_Y = train_Y.reshape(-1, 1, 1).astype('float32')
test_X = test_X.reshape(-1, 1, 3).astype('float32')
train_X = torch.from_numpy(train_X)
train_Y = torch.from_numpy(train_Y)
test_X = torch.from_numpy(test_X)
class RNN(nn.Module):
def __init__(self, input_size, hidden_size, output_size=1, num_layer=2):
super(RNN, self).__init__()
self.input_size = input_size
self.hidden_size = hidden_size
self.output_size = output_size
self.num_layer = num_layer
self.rnn = nn.RNN(input_size, hidden_size, batch_first=True)
self.linear = nn.Linear(hidden_size, output_size)
def forward(self, x):
out, h = self.rnn(x)
out = self.linear(out[:, -1, :])
return out
net = RNN(3, 20)
criterion = nn.MSELoss(reduction='mean')
optimizer = torch.optim.Adam(net.parameters(), lr=1e-2)
train_loss = []
test_loss = []
for e in range(1000):
pred = net(train_X)
loss = criterion(pred, train_Y)
optimizer.zero_grad()
loss.backward()
optimizer.step()
if (e + 1) % 100 == 0:
print('Epoch:{},loss:{:.10f}'.format(e + 1, loss.data.item()))
train_loss.append(loss.item())
plt.plot(train_loss, label='train_loss')
plt.legend()
plt.show()
# 预测值和真实值的代码
net.eval()
pred_test = net(test_X)
pred_test = pred_test.detach().numpy() * scalar
test_Y = test_Y.reshape(-1, 1) * scalar
plt.plot(pred_test, label='predict')
plt.plot(test_Y, label='true')
plt.legend()
plt.show()
```