机器学习（1）安装Pytorch
1.安装命令
pip3 install torch torchvision torchaudio --index-url https://download.pytorch.org/whl/cu1182.安装过程Log：
Looking in indexes: https://download.pytorch.org/whl/cu118
Collecting torch Downloading https://download.pytorch.org/whl/cu118/torch-2.6.0%2Bcu118-cp312-cp312-win_amd64.whl.metadata (28 kB)
Collecting torchvision Downloading https://download.pytorch.org/whl/cu118/torchvision-0.21.0%2Bcu118-cp312-cp312-win_amd64.whl.metadata (6.3 kB)
Collecting torchaudio Downloading https://download.pytorch.org/whl/cu118/torchaudio-2.6.0%2Bcu118-cp312-cp312-win_amd64.whl.metadata (6.8 kB)
Collecting filelock (from torch) Downloading https://download.pytorch.org/whl/filelock-3.13.1-py3-none-any.whl.metadata (2.8 kB)
Collecting typing-extensions>=4.10.0 (from torch) Downloading https://download.pytorch.org/whl/typing_extensions-4.12.2-py3-none-any.whl.metadata (3.0 kB)
Collecting networkx (from torch) Downloading https://download.pytorch.org/whl/networkx-3.3-py3-none-any.whl.metadata (5.1 kB)
Collecting jinja2 (from torch) Downloading https://download.pytorch.org/whl/Jinja2-3.1.4-py3-none-any.whl.metadata (2.6 kB)
Collecting fsspec (from torch) Downloading https://download.pytorch.org/whl/fsspec-2024.6.1-py3-none-any.whl.metadata (11 kB)
Collecting setuptools (from torch) Downloading https://download.pytorch.org/whl/setuptools-70.2.0-py3-none-any.whl.metadata (5.8 kB)
Collecting sympy==1.13.1 (from torch) Downloading https://download.pytorch.org/whl/sympy-1.13.1-py3-none-any.whl (6.2 MB) ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 6.2/6.2 MB 1.4 MB/s eta 0:00:00
Collecting mpmath<1.4,>=1.1.0 (from sympy==1.13.1->torch) Downloading https://download.pytorch.org/whl/mpmath-1.3.0-py3-none-any.whl (536 kB) ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 536.2/536.2 kB 975.3 kB/s eta 0:00:00
Collecting numpy (from torchvision) Downloading https://download.pytorch.org/whl/numpy-2.1.2-cp312-cp312-win_amd64.whl.metadata (59 kB)
Collecting pillow!=8.3.*,>=5.3.0 (from torchvision) Downloading https://download.pytorch.org/whl/pillow-11.0.0-cp312-cp312-win_amd64.whl.metadata (9.3 kB)
Collecting MarkupSafe>=2.0 (from jinja2->torch) Downloading https://download.pytorch.org/whl/MarkupSafe-2.1.5-cp312-cp312-win_amd64.whl (17 kB)
Downloading https://download.pytorch.org/whl/cu118/torch-2.6.0%2Bcu118-cp312-cp312-win_amd64.whl (2728.9 MB) ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 2.7/2.7 GB 5.9 MB/s eta 0:00:00
Downloading https://download.pytorch.org/whl/cu118/torchvision-0.21.0%2Bcu118-cp312-cp312-win_amd64.whl (5.3 MB) ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 5.3/5.3 MB 4.5 MB/s eta 0:00:00
Downloading https://download.pytorch.org/whl/cu118/torchaudio-2.6.0%2Bcu118-cp312-cp312-win_amd64.whl (4.0 MB) ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 4.0/4.0 MB 5.4 MB/s eta 0:00:00
Downloading https://download.pytorch.org/whl/pillow-11.0.0-cp312-cp312-win_amd64.whl (2.6 MB) ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 2.6/2.6 MB 4.9 MB/s eta 0:00:00
Downloading https://download.pytorch.org/whl/typing_extensions-4.12.2-py3-none-any.whl (37 kB)
Downloading https://download.pytorch.org/whl/filelock-3.13.1-py3-none-any.whl (11 kB)
Downloading https://download.pytorch.org/whl/fsspec-2024.6.1-py3-none-any.whl (177 kB)
Downloading https://download.pytorch.org/whl/Jinja2-3.1.4-py3-none-any.whl (133 kB)
Downloading https://download.pytorch.org/whl/networkx-3.3-py3-none-any.whl (1.7 MB) ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 1.7/1.7 MB 2.0 MB/s eta 0:00:00
Downloading https://download.pytorch.org/whl/numpy-2.1.2-cp312-cp312-win_amd64.whl (12.6 MB) ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 12.6/12.6 MB 1.3 MB/s eta 0:00:00
Downloading https://download.pytorch.org/whl/setuptools-70.2.0-py3-none-any.whl (930 kB) ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 930.8/930.8 kB 2.1 MB/s eta 0:00:00
Installing collected packages: mpmath, typing-extensions, sympy, setuptools, pillow, numpy, networkx, MarkupSafe, fsspec, filelock, jinja2, torch, torchvision, torchaudio
Successfully installed MarkupSafe-2.1.5 filelock-3.13.1 fsspec-2024.6.1 jinja2-3.1.4 mpmath-1.3.0 networkx-3.3 numpy-2.1.2 pillow-11.0.0 setuptools-70.2.0 sympy-1.13.1 torch-2.6.0+cu118 torchaudio-2.6.0+cu118 torchvision-0.21.0+cu118 typing-extensions-4.12.23.测试安装是否成功
Python 3.12.8 (tags/v3.12.8:2dc476b, Dec 3 2024, 19:30:04) [MSC v.1942 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import torch
>>> x = torch.rand(5, 3)
>>> print(x)
tensor([[0.7669, 0.8559, 0.1532], [0.0107, 0.3796, 0.5369], [0.0231, 0.3256, 0.6019], [0.8649, 0.0543, 0.6369], [0.4323, 0.0320, 0.3343]])4.查看本机是否有GPU
>>> torch.cuda.is_available()
False
>>>