树莓派4（32位Linux）Python环境numpy导入依赖错误求助

问题背景 #

在32位Linux系统的树莓派4上运行Python脚本时，出现numpy依赖缺失报错，尝试卸载重装numpy、使用虚拟环境等操作后仍未解决，当前尝试通过miniconda推进，但问题依旧。

核心错误信息 #

ImportError: Unable to import required dependencies: numpy
Original error was: libcblas.so.3: cannot open shared object file: No such file or directory

已执行的操作及反馈 #

1. Python版本确认 #

joy@raspberrypi:/ $ python --version
Python 3.9.2
joy@raspberrypi:/ $ python3 --version
Python 3.9.2

2. numpy卸载/重装尝试 #

joy@raspberrypi:/media/joy/DATA $ pip uninstall numpy
Found existing installation: numpy 1.19.5
Not uninstalling numpy at /usr/lib/python3/dist-packages, outside environment /usr
Can't uninstall 'numpy'. No files were found to uninstall.
joy@raspberrypi:/media/joy/DATA $ pip install --upgrade numpy
Looking in indexes: https://pypi.org/simple, https://www.piwheels.org/simple
Requirement already satisfied: numpy in /usr/lib/python3/dist-packages (1.19.5)
Collecting numpy
  Using cached https://www.piwheels.org/simple/numpy/numpy-1.23.4-cp39-cp39-linux_armv7l.whl (12.4 MB)
Installing collected packages: numpy
  WARNING: The scripts f2py, f2py3 and f2py3.9 are installed in '/home/joy/.local/bin' which is not on PATH.
  Consider adding this directory to PATH or, if you prefer to suppress this warning, use --no-warn-script-location.
Successfully installed numpy-1.23.4

3. 脚本运行报错 #

Traceback (most recent call last):
  File "/media/joy/DATA/excel_to_mDB.py", line 3, in <module>
    import pandas as pd
  File "/home/joy/.local/lib/python3.9/site-packages/pandas/__init__.py", line 16, in <module>
    raise ImportError(
ImportError: Unable to import required dependencies:
numpy:

IMPORTANT: PLEASE READ THIS FOR ADVICE ON HOW TO SOLVE THIS ISSUE!

Importing the numpy C-extensions failed. This error can happen for
many reasons, often due to issues with your setup or how NumPy was
installed.

Please note and check the following:

  * The Python version is: Python3.9 from "/usr/bin/python"
  * The NumPy version is: "1.23.4"

Original error was: libcblas.so.3: cannot open shared object file: No such file or directory

4. 虚拟环境操作问题 #

(venv) joy@raspberrypi:/media/joy/DATA $ python excel_to_mDB.py
Traceback (most recent call last):
  File "/media/joy/DATA/excel_to_mDB.py", line 3, in <module>
    import pandas as pd
ModuleNotFoundError: No module named 'pandas'
(venv) joy@raspberrypi:/media/joy/DATA $ sudo pip install pandas
Looking in indexes: https://pypi.org/simple, https://www.piwheels.org/simple
Requirement already satisfied: pandas in /usr/lib/python3/dist-packages (1.1.5)
(venv) joy@raspberrypi:/media/joy/DATA $ sudo pip uninstall pandas
Found existing installation: pandas 1.1.5
Not uninstalling pandas at /usr/lib/python3/dist-packages, outside environment /usr
Can't uninstall 'pandas'. No files were found to uninstall.

运行的脚本代码 #

import pandas as pd
from pymongo import MongoClient

aaa = pd.read_excel("T1_new.xls")

print(aaa.head)

client = MongoClient('127.0.0.1:27017')
db = client['sample_data_in_DB']
collection = db['sample_collection']

collection.insert_many(aaa.to_dict('records'))

解决方案 #

1. 安装缺失的系统底层库 #

报错根源是系统缺少libcblas.so.3，直接通过apt安装适配树莓派的线性代数基础库：

sudo apt update && sudo apt install libcblas3 libatlas-base-dev

2. 清理numpy版本冲突 #

当前系统存在两个numpy版本，导致路径混乱，按以下步骤修复：

• 移除用户本地安装的numpy：

pip uninstall numpy -y

• 用系统包管理器重新安装适配版本：

sudo apt install python3-numpy

3. 正确使用虚拟环境 #

之前误用sudo pip导致包安装到系统而非虚拟环境，正确操作流程：

• 激活虚拟环境：

source venv/bin/activate

• 直接用pip安装所有依赖（无需sudo）：

pip install pandas pymongo openpyxl

注：openpyxl是pandas读取xls/xlsx文件必需的依赖

4. 放弃miniconda（可选） #

树莓派32位系统的miniconda支持有限，容易出现架构不兼容问题，优先使用系统包管理器+piwheels源，piwheels已预编译ARM适配的Python包，兼容性更强。

内容的提问来源于stack exchange，提问作者j ton