PyTorch

PyTorch (https://pytorch.org/) is a deep learning library based on Torch and developed by Facebook. It is relatively easy to use, and has recently gained a lot of popularity. It will automatically select a GPU, if one is available, reverting to the CPU otherwise. If you wish to select the device explicitly, you could use the following code sample:

# at beginning of the script
device = torch.device("cuda:0" if torch.cuda.is_available() else "cpu")
...
# then whenever you get a new Tensor or Module
# this won't copy if they are already on the desired device
input = data.to(device)
model = MyModule(...).to(device)