[Python知识库]conda安装torch遇坑

想要安装torch，先在这个官网上得到和系统匹配的命令。

注意，现在torch版本v1.11暂时不支持算力sm86的GPU，如NVIDIA RTX3090，需要降级安装其他版本。否则报错：

CUDA error: no kernel image is available for execution on the device

查看pytorch支持的算力，和gpu算力：

import torch
torch.cuda.get_device_capability()

查看gpu的cuda版本nvidia-smi

如果安装报错

failed with initial frozen solve. Retrying with flexible solve.
或The environment is inconsistent, please check the package plan carefully
The following packages are causing the inconsistency:
或UnsatisfiableError: The following specifications were found
to be incompatible with the existing python installation in your environment:

首先尝试添加conda源（即channel）
ref

conda config # 创建.condarc文件
# 查看现在的channel状态和优先级
conda config --get channels
# 添加conda-forge channel并设置为最高优先级
conda config --add channels conda-forge

conda config --set channel_priority flexible
# 查看channel状态和优先级
conda config --get channels

如果不行就尝试pip安装：（最终是这么解决的）
ref

pip3 install torch==1.10.0+cu113 torchvision==0.11.1+cu113 torchaudio==0.10.0+cu113 -f https://download.pytorch.org/whl/cu113/torch_stable.html