Develop Reference

ModuleNotFoundError, even after pip install

I have recently bought a new laptop and was viewing some python projects of mine which I made on my pc. For one of them I use the python-bitvavo-api library which I installed using pip3 install python-bitvavo-api. The version I installed is 1.2.2 which is the latest on their website.
Now when I try to import it using this code: from python_bitvavo_api.bitvavo import Bitvavo, I get the following error:
Traceback (most recent call last):
File "C:\Users\indig\OneDrive\Documenten\Python Projects\Personal\Cryptone\Cryptone.py", line 6, in <module>
from python_bitvavo_api.bitvavo import Bitvavo
ModuleNotFoundError: No module named 'python_bitvavo_api'
I read online that it may occur when using multiple python versions, Im only using 1 and thats python 3.7
Btw. I have the same error with the Pillow module, so it might be a setting in visual studio that I dont know of. Anyway, someone please help. If you need more details please ask.

How are you running it? From the terminal or from VS?
You can also check the installed libraries running the command pip list

Trying to import python modules returns ModuleNotFound Error

Im attempting to use the numpy module in webots but whatever I try I always get
INFO: assignment_2_controller_2: Starting controller: python3.6 -u "assignment_2_controller_2.py"
[assignment_2_controller_2] Traceback (most recent call last):
[assignment_2_controller_2] File "assignment_2_controller_2.py", line 4, in <module>
[assignment_2_controller_2] import numpy
[assignment_2_controller_2] ModuleNotFoundError: No module named 'numpy'
WARNING: 'assignment_2_controller_2' controller exited with status: 1.
I have installed numpy with both pip2 and pip3 and neither seem to have made any difference and the package shows up in ~/.local/lib/python3.6/site-packages. I can also confirm that this module works in the python editor and in other python files.
Is there perhaps something I need to change in webots python Makefile or perhaps in my environment variables?
Edit:
Printing sys.path shows
'/snap/webots/14/usr/share/webots/lib/controller/python36', '/snap/webots/14/usr/lib/python36.zip', '/snap/webots/14/usr/lib/python3.6', '/snap/webots/14/usr/lib/python3.6/lib-dynload', '/snap/webots/14/usr/lib/python3/dist-packages'
I installed webots using snap but why wouldnt it use the python dictated by the PATH environment variable?
Fix:
By the looks of it snap creates a contained filesystem for webots to run in by design in which it installed its own python binaries. I therefore uninstalled webots with snap and then installed from the .deb file off their website and now it works fine.

Webots installed from the Snap package is running in a kind of sandbox, it is therefore using the version of Python distributed with the snap package (which you can't alter).
As explained in the documentation, you might use external controllers to launch yourself the controller instead of letting Webots starting it. This way you can chose which version of Python you want to use: https://cyberbotics.com/doc/guide/installation-procedure#installing-the-snap-package
Alternatively, you can use a different way to install Webots (from the Debian or archive package). The other installations are not coming with Python and are using the system Python.

Importing CV2 does not work in Spyder but works in PyCharm

I have Anaconda 3 installed (Python 3.6.3) and I am working on a project that uses the CV2 package in python. Now I am relatively new to python but I have been using this package (via "import cv2" command) in PyCharm with no problems. However, today, I wanted to give Spyder a try. I started using the IDE and everything was working. But all of a sudden, Spyder kept giving me an error when I try to import cv2. I really did not change anything and I only was debugging the script. The error I am getting is as follows:
"""
In [1]: import cv2
Traceback (most recent call last):
File "", line 1, in
import cv2
ImportError: DLL load failed: The specified procedure could not be found.
"""
I cannot figure out how this can be related to the IDE since PyCharm still can import it. Could anybody give me a hint please?

As I know CV2 is python 2x related. When You use CV2 You need copy cv2.pyd file directly to python 2x site-packages.

No module named cv

I'm trying to run this script:
https://github.com/openalpr/train-detector/blob/master/crop_plates.py
I've never dealt with python before. First of all I had some syntax errors in the print lines. They were lacking parentheses...but I'm not sure if I get this error because of the Python version I installed or this was indeed a syntax error. After fixing the syntax error I'm receiving the following error:
C:\>py crop_plates.py
Traceback (most recent call last):
File "crop_plates.py", line 7, in <module>
import cv2, cv
ImportError: No module named cv
I did the following:
Installed Python 2.7.5 32 bits.
Installed numpy 1.9.1 32 bits (also tried different versions)
Installed matplotlib 1.3.0.
Installed OpenCv
Copied cv2.pyd from
C:\Users\Me\Downloads\opencv\build\python\2.7\x86
to
C:\Python27\Lib\site-packages
But I can't find anywhere the cv.pyd file that I'm missing.
I found references to this guide for installing Opencv but it's not working
http://opencv.willowgarage.com/documentation/python/
Thank you very much,
Edit: I'm running Python in Windows 7.

For ImportError: No module named cv, try installing opencv-python module using below command:
pip install opencv-python

cv2.cv doesn't exists in OpenCV 3.0. Use simply cv2
Also, the attribute is no more CV_HOUGH_GRADIENT but HOUGH_GRADIENT
So what you looking for is probably:
cv2.HOUGH_GRADIENT

OK , I searched for a while and find the following :
First: you may write: import cv2.cv as cv to solve your proplem
cv and cv2 are both interface for python , and now , the newest "cv2" is the most used one , but clearly some libraries still use cv and others (like yours) use mix of the two,What is different between all these OpenCV Python interfaces?

It seems this code is using a old version of OpenCV. Unfortunately there is no mention of the exact version they used in their repo.
As the code is at least 2 years old, I would install opencv version 2.4.
pip install opencv-python==2.4

Installing Python/PyGame on mac

I've been trying to install PyGame with little success. I downloaded the
pygame-1.9.1release-python.org-32bit-py2.7-macosx10.3.dmg
version of PyGame from this link and installed it using the wizard, but when I typed import pygame into the IDLE I got the following message.
$ import pygame
Traceback (most recent call last):
File "<pyshell#0>", line 1, in <module>
import pygame
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pygame/__init__.py", line 95, in <module>
from pygame.base import *
ImportError: dlopen(/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pygame/base.so, 2): no suitable image found. Did find:
/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pygame/base.so: no matching architecture in universal wrapper
What did I do wrong?
Also, what are the prerequisites for PyGame? I'm doing all this on a new computer and I've hardly downloaded anything.
I'm running OS X Version 10.8.2.

I know this thread is a little old, but thought I'd share my experience on this subject...
I'm using a 64-bit MacBook Pro running OS Mavericks and python 2.7.
Steps:
If you've installed a few different versions of pygame while trying to get the darn thing to import and work successfully, make sure you delete/uninstall all of these to get a fresh start. I did a simple search in the terminal to see where all of the various pygame folders where located:
In Terminal: sudo find / -iname "pygame"
The results show a list of all the pygame directories, these are the folders that you want to delete. Note, I created a new tab in terminal to do this so I can reference the directories from the search on the previous tab and easily copy each directory without having to do another search to remember where they are:
In Terminal: sudo rm -R -i path/pygame
Also note, you can take the -i out of the above code and it won't confirm the deletion of certain files, but BE REALLY CAREFUL when deleting full directories from the terminal.
Once your machine is clean of all previous pygame installations, make sure you have python 2.7 from python.org, NOT IDLE (default Mac Python Interpreter)! This is very important. I use PyCharm and it rocks! Also, choose the version that works on a 32-bit machine and 64-bit machine - this way you won't have issues with the pygame 32-bit installer on your 64-bit machine. I tried same installation process but with the 64-bit only python 2.7 installation and it didn't work. Link provided below:
Download 32/64-bit Python 2.7
Next, download the 32-bit pygame file for OS X 10.3 and beyond and run the mpkg file created from the dmg. Link provided below.
Download pygame 1.910 release for python 2.7
You should now have a working pygame installation in your python 2.7 package library. Enjoy.

Did you install python from python.org? Or use the one that came with OS X?
If you used the one supplied by Apple, you must download the one from python.org first, then install using that package. Or you can try the Lion-pygame package (the link is at the bottom of the Macintosh section of the download page), but it may be incompatible.

Did you download python 64-bit or python 32-bit?
This can cause major problems if you don't have the right one, if you have 64-bit you can download pygame 64-bit from http://www.lfd.uci.edu/~gohlke/pythonlibs/#pygame