虽然正确安装了Numpy，但导入时出错的原因是什么

原始错误是：/usr/local/lib/python3.5/dist-packages/numpy/core//u multiarray\u umath.cpython-35m-arm-linux-gnueabihf.so:undefined symbol:cblas\u sgemm

如错误消息中所述，此错误有许多可能的原因，但是使用

--no-use-pep517

选项的

pip

对我有帮助。

您是否遵循了错误消息中的说明：尝试卸载并重新安装numpy并检查路径和PYTHONPATH？

when import numpy the following error was occur
Traceback (most recent call last):
  File "/usr/local/lib/python3.5/dist-packages/numpy/core/__init__.py", line 24, in <module>
    from . import multiarray
  File "/usr/local/lib/python3.5/dist-packages/numpy/core/multiarray.py", line 14, in <module>
    from . import overrides
  File "/usr/local/lib/python3.5/dist-packages/numpy/core/overrides.py", line 7, in <module>
    from numpy.core._multiarray_umath import (
ImportError: /usr/local/lib/python3.5/dist-packages/numpy/core/_multiarray_umath.cpython-35m-arm-linux-gnueabihf.so: undefined symbol: cblas_sgemm

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.5/dist-packages/numpy/__init__.py", line 142, in <module>
    from . import core
  File "/usr/local/lib/python3.5/dist-packages/numpy/core/__init__.py", line 54, in <module>
    raise ImportError(msg)
ImportError: 

Importing the numpy c-extensions failed.
- Try uninstalling and reinstalling numpy.
- If you have already done that, then:
  1. Check that you expected to use Python3.5 from "/usr/bin/python3.5",
     and that you have no directories in your PATH or PYTHONPATH that can
     interfere with the Python and numpy version "1.18.1" you're trying to use.
  2. If (1) looks fine, you can open a new issue at
     https://github.com/numpy/numpy/issues.  Please include details on:
     - how you installed Python
     - how you installed numpy
     - your operating system
     - whether or not you have multiple versions of Python installed
     - if you built from source, your compiler versions and ideally a build log

- If you're working with a numpy git repository, try `git clean -xdf`
  (removes all files not under version control) and rebuild numpy.