安装torch-sparse提示找不到torch模块，但torch已正常安装

问题背景 #

• 尝试安装指定仓库的旧版本依赖，使用Python 3.9创建虚拟环境，按要求先安装torch，再安装torch-scatter（安装成功）和torch-sparse（始终失败）
• 升级setuptools到最新版本后仍报错；在全新Python 3.12 + torch 2.5.1环境中，使用官方推荐命令安装后仍出现相同错误

报错信息 #

Collecting torch-sparse==0.6.15
Downloading torch_sparse-0.6.15.tar.gz (2.1 MB)
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 2.1/2.1 MB 1.1 MB/s eta 0:00:00
Installing build dependencies ... done
Getting requirements to build wheel ... error
error: subprocess-exited-with-error

× Getting requirements to build wheel did not run successfully.
│ exit code: 1
╰─> [17 lines of output]
Traceback (most recent call last):
File "C:\Users\caleb\Python\graph_transformer_2.venv\lib\site-packages\pip_vendor\pyproject_hooks_in_process_in_process.py", line 389, in <module>
main()
File "C:\Users\caleb\Python\graph_transformer_2.venv\lib\site-packages\pip_vendor\pyproject_hooks_in_process_in_process.py", line 373, in main
json_out["return_val"] = hook(**hook_input["kwargs"])
File "C:\Users\caleb\Python\graph_transformer_2.venv\lib\site-packages\pip_vendor\pyproject_hooks_in_process_in_process.py", line 143, in get_requires_for_build_wheel
return hook(config_settings)
File "C:\Users\caleb\AppData\Local\Temp\pip-build-env-jv3dantt\overlay\Lib\site-packages\setuptools\build_meta.py", line 334, in get_requires_for_build_wheel
return self._get_build_requires(config_settings, requirements=[])
File "C:\Users\caleb\AppData\Local\Temp\pip-build-env-jv3dantt\overlay\Lib\site-packages\setuptools\build_meta.py", line 304, in _get_build_requires
self.run_setup()
File "C:\Users\caleb\AppData\Local\Temp\pip-build-env-jv3dantt\overlay\Lib\site-packages\setuptools\build_meta.py", line 522, in run_setup  
super().run_setup(setup_script=setup_script)
File "C:\Users\caleb\AppData\Local\Temp\pip-build-env-jv3dantt\overlay\Lib\site-packages\setuptools\build_meta.py", line 320, in run_setup  
exec(code, locals())
File "<string>", line 8, in <module>
ModuleNotFoundError: No module named 'torch'
[end of output]
note: This error originates from a subprocess, and is likely not a problem with pip.
error: subprocess-exited-with-error

× Getting requirements to build wheel did not run successfully.
│ exit code: 1
╰─> See above for output.

当前环境信息 #

• Python版本：

$ python --version
Python 3.9.0
(.venv) 

• pip版本：

$ python -m pip --version
pip 25.0.1 from C:\Users\caleb\Python\graph_transformer_2\.venv\lib\site-packages\pip (python 3.9)
(.venv)

• torch安装信息：

$ pip show torch
Name: torch
Version: 2.6.0
Summary: Tensors and Dynamic neural networks in Python with strong GPU acceleration
Home-page: https://pytorch.org/
Author: PyTorch Team
Author-email: packages@pytorch.org
License: BSD-3-Clause
Location: c:\users\caleb\python\graph_transformer_2\.venv\lib\site-packages
Requires: filelock, fsspec, jinja2, networkx, sympy, typing-extensions
Required-by: PyGCL
(.venv)

疑问 #

问题是否出在setuptools？

解决思路 #

1. 使用预编译轮子安装（优先推荐）
   旧版本torch-sparse源码编译时依赖torch，但pip的隔离构建环境默认不包含已安装的torch。直接使用对应版本预编译包，避免源码编译：

# 替换cuXX为你的CUDA版本（如cu118、cu121），CPU版本用cpu
pip install torch-sparse==0.6.15 -f https://data.pyg.org/whl/torch-2.6.0+cuXX.html

2. 禁用pip隔离构建环境
   如果必须源码编译，让pip在当前虚拟环境中构建，而非隔离环境：

pip install torch-sparse==0.6.15 --no-build-isolation

3. 降级setuptools版本
   最新版setuptools可能与旧版torch-sparse的setup.py不兼容，尝试降级到兼容版本：

pip install setuptools==65.5.0

之后再重新安装torch-sparse

内容的提问来源于stack exchange，提问作者Caleb Stam