device is not None
时间: 2024-01-24 13:04:05 浏览: 26
The statement "device is not None" is typically used in PyTorch code to check if a device (such as CPU or GPU) has been specified for running the code. If a device has been specified, the code will run on that device, otherwise it will use the default device.
For example, the following code checks if a GPU has been specified and assigns the device accordingly:
```
import torch
device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
if device is not None:
print("Using device:", device)
else:
print("No device specified, using default device:", torch.device("cpu"))
```
In this case, if a GPU is available, the code will print "Using device: cuda", otherwise it will print "No device specified, using default device: cpu".