Enviro+ display not working in Python3

Support
1

Fresh install of the library and dependancies for the Enviro+ hat on RPi
Everything else works out of the box (so far) but the LCD won’t work if I run it in python 3. The error is as follows:

pi@rpi:~/enviroplus-python/examples $ python3 lcd.py
Traceback (most recent call last):
  File "/usr/local/lib/python3.7/dist-packages/numpy/core/__init__.py", line 22, in <module>
    from . import multiarray
  File "/usr/local/lib/python3.7/dist-packages/numpy/core/multiarray.py", line 12, in <module>
    from . import overrides
  File "/usr/local/lib/python3.7/dist-packages/numpy/core/overrides.py", line 7, in <module>
    from numpy.core._multiarray_umath import (
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 "lcd.py", line 3, in <module>
    import ST7735
  File "/usr/local/lib/python3.7/dist-packages/ST7735-0.0.4-py3.7.egg/ST7735/__init__.py", line 23, in <module>
    import numpy as np
  File "/usr/local/lib/python3.7/dist-packages/numpy/__init__.py", line 140, in <module>
    from . import core
  File "/usr/local/lib/python3.7/dist-packages/numpy/core/__init__.py", line 48, in <module>
    raise ImportError(msg)
ImportError: 

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.

We have compiled some common reasons and troubleshooting tips at:

    https://numpy.org/devdocs/user/troubleshooting-importerror.html

Please note and check the following:

  * The Python version is: Python3.7 from "/usr/bin/python3"
  * The NumPy version is: "1.19.4"

and make sure that they are the versions you expect.
Please carefully study the documentation linked above for further help.

Original error was: libf77blas.so.3: cannot open shared object file: No such file or directory

The example runs fine in python2, but not python 3.x.

I installed via the single-line install as per the documentation and have rebooted. Any leads on getting numpy to play nice in py3?

2

Try the following and have another go.
sudo apt-get update
sudo pip install st7735
sudo pip3 install st7735
sudo apt-get install python-rpi.gpio python-spidev python-pip python-imaging python-numpy
sudo apt-get install python3-rpi.gpio python3-spidev python3-pip python3-imaging python3-numpy

3

Worked without errors, except one pointing out that python3-imaging has been replaced by python3-pil

The error persists though, but only in python3

4

Looks like a NumPy error, solved with

sudo apt-get install libatlas-base-dev
5

OK, glad you sorted it out. I have a bunch of those displays and run modified Enviro / Enviro+ code on them. I don’t own an Enviro or Enviro+ though. I haven’t started over from scratch in a while, over a year I think?