Develop Reference

Installing pip and numpy on Unix server without root access

I know this question has been asked and answered a number of times but none of those solutions have worked for me. I have installed Python 2.7 into a local directory and added it to my path. When I try to install numpy i get the following error:
ImportError: No module named setuptools
I cannot simply sudo apt-get install python-setuptools because i don't have root access.
I need to install numpy and ideally have pip working for future applications.

0) Try to install packages that are isolated to the current user, use the --user flag:
pip install --user SomeProject
1a) I agree with #Pi Marillion here, use an isolated conda environment if you don't have root access. This way you keep your path clean.
To install conda:
Since I don't know about your OS, go to https://docs.conda.io/en/latest/miniconda.html
After installation, update your conda (just in case):
conda update conda
To list the installed packages, you can do
conda list
You should see python installed. you can start an interpreter by typing python in the terminal.
There's conda cheat sheet that I found incredibly helpful:
https://docs.conda.io/projects/conda/en/latest/user-guide/cheatsheet.html
b) Now try installing via pip and I think you might need python 3.x for setuptools.
https://packaging.python.org/tutorials/installing-packages/#id13
2) If this does not work you can still try
https://packaging.python.org/guides/installing-stand-alone-command-line-tools/
Hope this helps :)

First try easy_install --user setuptools pip. If that doesn't work you need to install things manually.
Download setuptools-*.zip from https://pypi.org/project/setuptools/#files. Unzip the archive, cd into the new directory and run python2.7 setup.py install.
Then try pip install. If it still doesn't work reinstall pip: download get-pip.py and run python get-pip.py --user.

bash: virtualenv: command not found "ON Linux"

I am using a form of Lubuntu called GalliumOS (optimized for Chromebooks). I installed pip using $ sudo apt-get install python-pip. I then used pip install --user virtualenv and pip install virtualenv, and then when I tried to subsequently use virtualenv venv I experienced the message bash: virtualenv: command not found.
Between the pip installs above, I used pip uninstall virtualenv to get back to square one. The error remained after a reinstall.
I read several other posts, but all of them seemed to deal with similar problems on MacOS. One that came close was installing python pip and virtualenv simultaneously. Since I had already installed pip, I didn't think that these quite applied to my issue. Why is pip install virtualenv not working this way on LUbuntu / GalliumOS?

Are you sure pip install is "failing"? To me, it sounds like the directory to which pip is installing modules on your machine is not in your PATH environment variable, so when virtualenv is installed, your computer has no idea where to find it when you just type in virtualenv.
Find where pip is installing things on your computer, and then check if the directory where the pyenv executable is placed is in your PATH variable (e.g. by doing echo $PATH to print your PATH variable). If it's not, you need to update your PATH variable by adding the following to your .bashrc or .bash_profile or etc.:
export PATH="PATH_TO_WHERE_PIP_PUTS_EXECUTABLES:$PATH"

What finally worked for me was this. I used
$ sudo apt-get install python-virtualenv.
I was then able to create a virtual environment using $ virtualenv venv.
I was seeking to avoid using $ sudo pip install virtualenv, because of admonitions in other posts to not do this, and agreed, because of experiences I'd had with subsequent difficulties when doing this.

pip install virtualenv
This command worked for me for. This problem that raised to me on Kali Linux.

Virtualenv not detecting pip3

I'm having problems running pip3 from virtualenv. If I run 'pip3 install django' in my active virtualenv, it will try to install it in my virtualenv, but fail because need privileges. The problem is, that when I use 'sudo pip3 install django', installs django globally. How can I avoid that?

SOLUTION
I solved it reinstalling virtualenv.
Thanks to Klaus D.
ALTERNATIVE SOLUTION
If everything else fail, you can still use pip explicitly:
myvirtualenv/bin/pip3 install django==1.7.1
and when you create your virtualenv do it without sudo, like:
virtualenv myvirtualenv --no-site-packages
Thanks to cesarkawakami from #python freenode irc.

Pip install forced into global environment, when virtualenv is active

When trying (on a MacOS 10.8.5) to install packages into an activated virtual environment, pip fails with error:
source env/bin/activate
pip install somepackage
...
error: could not create '/Library/Python/2.7/site-packages/somepackage': Permission denied
I've been using pip for a long without this issue. There are lots of similar questions and the answers suggest to use sudo pip install ..., however so far could not find a way to fix pip so that packages go inside the virtual environment, instead of the global one.
Also, I've tried adding --install-option="--prefix=env", but ran into other error. This is really unusual, haven't seen this issue in years of using pip.
Does anyone have a clue? Thanks!

Self-answer. I've ran:
deactivate
virtualenv env
source env/bin/activate
pip install somepackage
That is created virtualenv right on top of the existing one - in the same directory and the problem was solved, even though I could not find an explanation.

pip freeze does not show all installed packages

I am using a virtualenv. I have fabric installed, with pip. But a pip freeze does not give any hint about that. The package is there, in my virtualenv, but pip is silent about it. Why could that be? Any way to debug this?

I just tried this myself:
create a virtualenv in to the "env" directory:
$virtualenv2.7 --distribute env
New python executable in env/bin/python
Installing distribute....done.
Installing pip................done.
next, activate the virtual environment:
$source env/bin/activate
the prompt changed. now install fabric:
(env)$pip install fabric
Downloading/unpacking fabric
Downloading Fabric-1.6.1.tar.gz (216Kb): 216Kb downloaded
Running setup.py egg_info for package fabric
...
Successfully installed fabric paramiko pycrypto
Cleaning up...
And pip freeze shows the correct result:
(env)$pip freeze
Fabric==1.6.1
distribute==0.6.27
paramiko==1.10.1
pycrypto==2.6
wsgiref==0.1.2
Maybe you forgot to activate the virtual environment? On a *nix console type which pip to find out.

You can try using the --all flag, like this:
pip freeze --all > requirements.txt

Although your problem was specifically due to a typo, to help other users:
pip freeze doesn't show the dependencies that pip depends on. If you want to obtain all packages you can use pip freeze --all or pip list.

If you have redirected all the pre-installed packages in a file named pip-requirements.txt then it is pretty simple to fix the above issue.
1) Delete your virtualenv folder or create new one (I am giving it a name as venv)
rm -rf venv && virtualenv venv
2) Install all the requirements/dependencies from the pip-requirements.txt
pip install -r pip-requirements.txt
3) Now you can check the installed packages for your Django application
pip freeze
4) If you had forgotten to update your requirements file(pip-requirements.txt), then install fabric again (Optional Step)
Note: After installing any dependency for your Django app, always update the requirements in any file as follows (make sure your virtualenv is activated)
pip freeze > pip requirements.txt
That's it.

Adding my fix in addition of above fix also ,
I was also facing the same issue on windows,even after activating the virtualenv too pip freeze was not giving me all list of installed packages. So i upgraded my pip with python -m pip install --upgrade pip command and then used pip freeze.
This time it worked and gave me all list of installed packages.

This might be stupid but I have got the same problem. I solved it by refreshing vs code file directory (inside vscode there is a reload button). :)

If none of the above answers are working for you.
As with me you might have problem in you venv and pip configuration.
Go inside your venv/bin and open pip and see the 2nd line as:
'''exec' "path/to/yourvenv/bin/python3" "$0" "$#"
See if this line is correctly pointing inside your venv or not
For example in my case.
I initially named my virtual environment as venv1
and later just renamed it to venv2.
In doing so my pip file 2nd line had: '''exec' "venv1/bin/python3" "$0" "$#"
which to work properly should have: '''exec' "venv2/bin/python3" "$0" "$#" notice "venv2" not "venv1" since venv1 in now renamed to venv2.
Due to this python was looking inside pip of venv2 and throwing error or not working as desired.

For those who added Python modules via PyCharm IDE, after generating a virtual environment from the command prompt, good luck! You will need to rebuild the requirements.txt file manually with the ones missing by first running pip3 freeze and adding what is missing from PyCharm.
I highly suggest switching to Visual Studio Code.