Upgrading to Latest Numpy Version on Raspberry Pi 3

Question

I'm not sure if this is a Raspberry Pi issue, Raspbian Issue, Python Issue, or all of the above. So forgive me if this is the wrong place to ask this.

I just got me a Raspberry Pi 3B+ and installed the latest Raspbian image on the SD card for it. In other words, it's a "clean slate".

When I go into Python (3.5), and type "Import numpy", numpy imports with no problem. This is the Numpy provided by the image, and NOT the numpy I try to install from pip (version 1.12.1 to be exact).

When I try to upgrade to the latest version however (version 1.15.4), using "pip3 install numpy", it seems to install ok, but when I go to import it, I get the following:

**Traceback (most recent call last):
  File "/home/pi/.local/lib/python3.5/site-packages/numpy/core/__init__.py", line 16, in <module>
    from . import multiarray
ImportError: libf77blas.so.3: cannot open shared object file: No such file or directory
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/pi/.local/lib/python3.5/site-packages/numpy/__init__.py", line 142, in <module>
    from . import add_newdocs
  File "/home/pi/.local/lib/python3.5/site-packages/numpy/add_newdocs.py", line 13, in <module>
    from numpy.lib import add_newdoc
  File "/home/pi/.local/lib/python3.5/site-packages/numpy/lib/__init__.py", line 8, in <module>
    from .type_check import *
  File "/home/pi/.local/lib/python3.5/site-packages/numpy/lib/type_check.py", line 11, in <module>
    import numpy.core.numeric as _nx
  File "/home/pi/.local/lib/python3.5/site-packages/numpy/core/__init__.py", line 26, in <module>
    raise ImportError(msg)
ImportError: 
Importing the multiarray numpy extension module failed.  Most
likely you are trying to import a failed build of numpy.
If you're working with a numpy git repo, try `git clean -xdf` (removes all
files not under version control).  Otherwise reinstall numpy.
Original error was: libf77blas.so.3: cannot open shared object file: No such file or directory**

When I type "pip3 uninstall numpy", it successfully removes the 1.15.4 version, and replaces it with the 1.12.1 version. I even tried typing "pip3 uninstall numpy" AGAIN to see if it would remove the 1.12.1 version, but I get the following:

**Not uninstalling numpy at /usr/lib/python3/dist-packages, outside environment /usr**

The funny thing is, I tried (just for kicks) installing numpy with "pip install numpy" for Python 2.7, and there were no problems at all importing it. But I want to use Python 3, not 2. I don't recall having this much problems with one of the earlier versions of Raspbian, and I THINK it has to do something with Numpy coming preinstalled in the image.

Thanks for any replies!

Chris

Answer 1

First of all I'm assuming you're running Raspbian Stretch.

What I would do is uninstall old numpy version, install prerequisites and then install numpy again.

sudo apt update
sudo apt remove python3-numpy
sudo apt install libatlas3-base
sudo pip3 install numpy

Don't use sudo with pip3 installif you're installing numpy in a virtual environment. I can also not quite make out if you have a locally installed numpy, so you could run pip3 uninstall numpy (without sudo) first.