Develop Reference

How to integrate ns3 module with pycharm?

I'm new to the ns3, and I was trying to integrate ns3 to PyCharm cause I'm familiar with PyCharm. It seems that ns3 is installed correctly on my machine, running ./waf python works fine but when I use ./waf shell, there are some modules it couldn't find, such as ns.application...etc. So, when I try the solution on this page: add waf libraries to PyCharm, it doesn't work too. Could anyone help me to solve this issue? I would really really appreciate it. By the way, the file I test was the sample from ns3: ns3_root/source/example/tutorial/first.py.

If you have enabled the python bindings and have built them, you need to add the ns3_root/build/bindings/python to the environment variable PYTHONPATH. After that running first.py should work.
You can do that running
export PYTHONPATH=$PYTHONPATH:/path/to/ns3_root/build/bindings/python
Or select first.py, edit the target settings and add that environment variable.
Or if you want this to persist, add this line to the end of the ~/. bashrc file.

in IntelliJ, showing "No module named xxx", but "xxx" is actually installed in my system

My IntelliJ version is 15.0.3, and have python plugin installed.
And when I open a python file in IntelliJ it's like below
Situation here is like below:
when I import these flagged modules in terminal, everything works fine.
running this python file in IntelliJ, is also fine
It's only the red underlying warning annoying me.
I tried this one, this one and this one, but none works for me.
Could anyone please tell me how to get rid of it? Thanks a lot.

You have to add the site-packages path of your interpreter.
For that you have to:
go to Project Structure
choose Global Libraries
choose your Python interpreter
press + at the upper left corner
choose the site-package path of your interpreter
choose "Classes"
also add your python interpreter root directory in the same way.

I have similar problems: cannot import manually installed module. I try to add classpath in Mac environment parameters and intellij SDKs, but it doesn't work. My final solution is to add the classpath of the module to Run/Debug Configurations:
Open Run/Debug Configurations and select your unittest class:
Run --> Edit Configurations...
Add your module's classpath to Environment variables:

Pycharm unresolved reference in virtualenv

When I started a new project in Pycharm using virtual environment, I got an unresolved reference warning message.
But I have installed django to my virtual environment and this code is working correctly.
How can I fix this? I'm using PyCharm 4.5.2 Pro

Open your project in pycharm and follow the step:
click on file(on top) > settings > project interpreter > add local > select virtualenv
OR
Make sure your project is a root directory, make it is the root directory.

I eventually stumbled across a method that worked for me, but I don't know the underlying problem.
Initially I created a virtualenv with PyCharm in the interpreter options. Annoyed that I was having this problem, I deleted it and just created a virtualenv with the virtualenv command, but the problem remained.
Then I went back to the interpreter selector and picked "add local". I navigated to the python binary in the /bin folder of the virtualenv I created and selected it. After this, the unresolved references were fixed.

I think your problem is like mine. I tested import matplotlib in the python shell, and it works, but in Pycharm it shows an error. This is because Pycharm doesn't know the path of site-packages.
To fix this, you can do one of the following:
Add the path of site-packages (for me C:\Program Files\Python 3.5\lib\site-packages) to PATH.
Go to File -> Settings -> Project Interpreter, then choose Python real path instead of venu path.
In your code add the following:
.
import sys
sys.path.append(r"C:\Program Files\Python 3.5\lib\site-packages")
import matplotlib.pyplot as plt
I think it will help you :)

File > Settings > Project > Project Structure
Double Click on the folder link under Content Root, and do OK.

Check your project root directory. Maybe problem in it.
And did you create virtualenv manually or through PyCharm?

Python works in PyCharm but not from terminal

I recently figured out how to import modules for unittesting in python. As a solution to this, I use:
sys.path.append(os.path.abspath(os.path.join(os.path.dirname(__file__), '..')))
from Dev.test import someclass
This works fine while running in PyCharm and I get the expected output. However, when I run from terminal I run into an error:
ImportError: No module named Dev.test
I have the init files where they are supposed to be but I'm lost as to why this is working in PyCharm but not from the terminal. I have not changed my path or anything in PyCharm as this code is supposed to be able to run with minimal modifications on other machines. Any idea as to why this is happening and what I might be able to do to fix it?
My folder structure is as follows
-Current
-Dev
-__init__.py
-test
- __init__.py
-someclass.py
-Tests
-__init__.py
-someunittest.py
I have tried running someunittest from the main folder as well as with a complete path but it only works in PyCharm

sys.path.append(os.getcwd()[:os.getcwd().index('Dev')])
I added this to my imports and it seems to have solved the problem. However, this doesn't seem like it would be the right way to do it; it will do for now.

When running a script from within PyCharm, it runs it in an environment with PYTHONPATH set to the list of all the folders that are marked "Sources Root" (with a blue folder icon) in the project explorer.
Outside of PyCharm, PYTHONPATH is not normally set. The first entry in sys.path refers to the current working directory where the script was run from. As long as you run your script with your terminal's working directory as the folder containing Dev, it should be able to find the Dev.test module, regardless of the extra entry added to sys.path.
Once you get the working directory correct, you should be able to remove the sys.path hack.

What #codewarrior has said about the PyCharm setting its own PYTHONPATH is correct. But sys.path didn't have my current working directory. So to get around this problem, I updated my PYTHONPATH (or you can edit sys.path).
Setting PYTHONPATH
export PYTHONPATH=$PYTHONPATH:`pwd` (OR your project root directory)
Updating sys.path
import sys
sys.path.insert(0,'<project directory>') OR
sys.path.append('<project directory>')
You can use insert/append based on the order in which you want your project to be searched.
HTH.

Pycharm uses a virtual environment. When you try run your program in your terminal this enviroment isn't active.
You need to build or upload your enviroment Pycharm with your libraries.
cd to the directory project and write in terminal:
source venv/bin/activate

I too have had this issue - and the PYTHONPATH setting set by PyCharm did seem to be the issue.
My alternative (as I was nearly finished writing the code) was to generate a setup.py - and install the classes/structure in my local virtual Python environment.

I would recommend trying out $ pip install . in your source directory. This will install your own packages for your project.

To add to similar answers here, PyCharm is doing some extra config for you before running your script. If adding your sources root to PYTHONPATH doesn't work then examine your run configuration in PyCharm for the script in question, there will likely be some more behind the scenes magic at play.

I had similar problem. I think the problem is that Pycharm modifies PYTHONPATH so before running your script:
cd to the file where python file resides
run export PYTHONPATH=.
run the script
You can also create "main" python file where you set the python path and then call the other modules

Unresolved import: models

I'm doing my VERY first project using python/django/eclipse/pydev following this guide
http://docs.djangoproject.com/en/dev/intro/tutorial01/
My only addition is the use of Eclipse/pydev.
I'm getting many errors related to "Unresolved imports". I can remove the errors using "remove error markers" and my site runs perfect (I can browse it) but I want to get rid definitively of this problem since errors pop up again after I removed them.
Any ideas?
EDIT
Using Ubuntu 9.1

Check your pythonpath. You need to include the parent directory of django, usually Lib/site-packages.

I'm on Mac OS X, but all I had to do was to add:
/Library/Python/2.6/site-packages
to my System PYTHONPATH (Found in: Preferences > Pydev > Interpreter - Python)
The equivalent for Ubuntu 10.04 would be:
/usr/lib/pymodules/python2.6
I'm guessing that the equivalent for Ubuntu 9.x could be:
/usr/lib/python2.6/site-packages
If it isn't and you're tired of looking, just upgrade to Ubuntu 10.04 and you should be fine.

I was able to get rid of the import errors executing this cmd
sudo ln -s /usr/lib/pymodules/ /usr/lib/python2.6/pymodules
I was lucky, testing different things I could resolve it but I'm not sure why I have to do this and how I could avoid doing it.

"Unresolved imports" occur when Eclipse/Pydev does not know what you want to import. Check your Pydev settings in the Eclipse preferences > Interpreter Python. Your site-packages folder and things you want to import should be there in the Pythonpath.
Also see http://pydev.org/manual_101_interpreter.html

Even if Lib/site-packages is added to the PYTHONPATH, this problem may happen when using modules from egg packages installed using easy_install. The problem with those, and that might actually depend on the easy_install version, is that by default they don't get installed directly inside Lib/site-packages but rather under a folder containing the full package name and having the .egg suffix. For example: Lib/site-packages/django_celery-3.0.23-py2.7.egg
Each module coming from packages installed as above needs an individual entry in PYTHONPATH. If the packages are installed after PyDev has been installed on the system, the system PYTHONPATH needs to be updated in PyDev. That is done automatically by going to Window -> Preferences -> PyDev -> Select your intepreter -> in the python interpreters panel remove and re-add your current python interpreter (usually, this should be the python executable from the system). Then a PyDev restart (File -> Restart) should solve the "Unresolved import" errors.

If you are facing problem of unused imports then I must say use Eclipse as a IDE as it is providing functionality to remove unused imports by pressing keys ctr+shift+O. Or In Eclipse there is plugin also available which is doing the same thing automatically when you save your code.You can get that plugin from eclipse plugin site easily and free of cost.

In my case of the modules were dependent on setuptools-14.3.1 , which was causing all these problems. After installation of setuptools-14.3.1 rest of the modules automatically resolved.

I was having a single import error when working in PyDEV in eclipse.
I was importing it like
from xyz_module import abc
So I clicked "Ctl + 1" and "select Unresolved import error" in eclipse and it created a class
file in a python file.
It turned out that I had created an application called "xyz_module" and a "xyz_module.py" file (with the same name that is) and this was causing an import error. I changed the python file to a new name and this resolved the error.

I had the same error and none of the answers worked for me as there was no PYTHONPATH options under Window -> Preferences -> PyDev -> Python.
Instead I added PYTHONPATH setting in the menu:
Project -> PyDev-PYTHONPATH -> External Libraries -> Add Source folder
I added the path of site-packages like
/home/Documents/hcx/venv/lib/python3.5/site-packages
Now PyDev stopped complaining.