pip安装更换镜像

使用pip来安装python包有时候安装起来会非常慢，因此需要换成国内的源来加速下载：

使用命令

以Torch为例：

pip install -i https://pypi.tuna.tsinghua.edu.cn/simple torch

若无法连接

WARNING: The repository located at pypi.doubanio.com is not a trusted or secure host and is being ignored. If this repository is available via HTTPS we recommend you use HTTPS instead, otherwise you may silence this warning and allow it anyway with '--trusted-host pypi.doubanio.com'.

ERROR: Could not find a version that satisfies the requirement opencv-python (from versions: none)

ERROR: No matching distribution found for opencv-python

可以将源中的http改为https

需要user

Could not install packages due to an EnvironmentError: [Errno 13] Permission denied: '/anaconda3/lib/python3.7/site-packages/llvmlite-0.28.0.dist-info'

Consider using the --user option or check the permissions.

需要加上--user：pip install 改为 pip install --user

pip install --user -i https://pypi.tuna.tsinghua.edu.cn/simple torch

审核编辑 hhy