I have import psycopg2 in my code yet I keep getting ImportError: No module named psycopg2when I try to run it. I've tried
└─$ pip3 install psycopg2
└─$ pip install psycopg2-binary
└─$ sudo apt-get install build-dep python-psycopg2
anyone have a solution to this?
The issue here is: Which Python version do you want to have psycopg2? I am posting 2 solutions, since I'm not sure which one is helpful in your case:
If you want to install it for Python 2, python -m pip install psycopg2 should do this.
If you want to install the package for Python 3, you can run python3 -m pip or pip3. This should avoid confusions with Python 2 installations.
I have installed mesa via:
$ pip install mesa
but it is automatically installing it into
/Users/MyName/Documents/User/lib/python2.7/site-packages/mesa/~
which means that when I try to run it with a Python 3 kernel, it can't find the module and I receive the error
ModuleNotFoundError: No module named 'mesa'
Could someone help me out? I'm assuming the problem is that it is automatically installed into the python 2.7 directory - how can i change this?
Thanks
To install packages for Python3 while exists Python2,
try this
python3 -m pip install xxx
or this
sudo apt install pip3
pip3 install xxx
You should use pip3 instead of pip:
pip3 install mesa
If you don't have pip3 install it using:
sudo apt-get update
sudo apt-get -y install python3-pip
If it doesn't work you can do it manually using curl:
curl "https://bootstrap.pypa.io/get-pip.py" -o "get-pip.py"
python get-pip.py
You can also execute it straight from python3:
python3 -m pip install mesa
It is always a good practice to set pip command to be equivalent to your python command. i.e, if python points to python3, you better change pip to point to pip3. Add alias pip='pip3' to your ~/.bash_profile file.
I am trying to use the qrtools module with Python 3.4.2 on my Raspberry Pi 2, however it cannot run as I don't have the zbar module installed.
Trying
pip-3.2 install zbar
Gives the error message shown in the picture
sudo pip-3.2 install zbar
gives a similar error
Any ideas?
(I do have it installed with Python 2.7)
UPDATE: Both libzbar-dev and python3-dev are up to date. Still...
No module named 'zbar'
assuming you're using a debian derivative (like ubuntu), you need to install zbar's developement package, which contains the header file zbar.h
$ sudo apt-get install libzbar-dev
for redhat/fedora systems:
$ sudo yum install zbar-devel
and probably python's dev package too:
$ sudo apt-get install python3-dev
or you can use pip install zbar-py
https://pypi.org/project/zbar-py/
Try the following code after entering sudo mode:
yum install zbar-devel
This should work for fedora.
Bumping #herve solution
On ubuntu and on Mint
sudo apt-get install python-zbar libzbar-dev python-qrtools
pip install libzbar-cffi==0.2.1
Just started Python a few days ago and I'm using PyCharm to develop a web application with Django. I have libpq-dev python-dev packages already installed, but it's still throwing me the same error:
./psycopg/psycopg.h:30:20: fatal error: Python.h: No such file or directory
which according to Google is the issue that occurs when python-dev package isn't installed. Note that I'm running the install from within the PyCharm interface for a virtualenv that I created for 3.2 and 3.3 (not sure how to run it from the terminal). Installing outside of the virtualenv still throws the same error, even when I install it from the terminal with setup.py. If I run pip install psycopg2 from the terminal, it succeeds, but it installs for Python 2.7. According to their website, they have support for up to Python 3.2.
On Ubuntu you just run this:
sudo apt-get install python3-psycopg2
Just run this using the terminal:
$ sudo apt-get install python3-dev
This way, you could use gcc to build the module you're trying to use.
Another option that seems to provide a newer version of psycopg2 than the one in the python3-psycopg2 package (at least when I wrote this):
sudo apt-get install pip3
sudo apt-get install libpq-dev
sudo pip3 install psycopg2
For most operating systems, the quickest way to install Psycopg is using the wheel package available on PyPI:
$ pip install psycopg2-binary
Check:
$ pip freeze | grep -i psycopg2
psycopg2-binary==2.9.3
This will install a pre-compiled binary version of the module which does not require the build or runtime prerequisites.
Or:
$ sudo apt-get install libpq-dev
$ pip install psycopg2
Check:
$ pip freeze | grep -i psycopg2
psycopg2==2.9.3
More info about psycopg vs psycopg-binary.
I have both python2.7 and python3.2 installed in Ubuntu 12.04.
The symbolic link python links to python2.7.
When I type:
sudo pip install package-name
It will default install python2 version of package-name.
Some package supports both python2 and python3.
How to install python3 version of package-name via pip?
Ubuntu 12.10+ and Fedora 13+ have a package called python3-pip which will install pip-3.2 (or pip-3.3, pip-3.4 or pip3 for newer versions) without needing this jumping through hoops.
I came across this and fixed this without needing the likes of wget or virtualenvs (assuming Ubuntu 12.04):
Install package python3-setuptools: run sudo aptitude install python3-setuptools, this will give you the command easy_install3.
Install pip using Python 3's setuptools: run sudo easy_install3 pip, this will give you the command pip-3.2 like kev's solution.
Install your PyPI packages: run sudo pip-3.2 install <package> (installing python packages into your base system requires root, of course).
…
Profit!
You may want to build a virtualenv of python3, then install packages of python3 after activating the virtualenv. So your system won't be messed up :)
This could be something like:
virtualenv -p /usr/bin/python3 py3env
source py3env/bin/activate
pip install package-name
Short Answer
sudo apt-get install python3-pip
sudo pip3 install MODULE_NAME
Source: Shashank Bharadwaj's comment
Long Answer
The short answer applies only on newer systems. On some versions of Ubuntu the command is pip-3.2:
sudo pip-3.2 install MODULE_NAME
If it doesn't work, this method should work for any Linux distro and supported version:
sudo apt-get install curl
curl https://bootstrap.pypa.io/get-pip.py | sudo python3
sudo pip3 install MODULE_NAME
If you don't have curl, use wget. If you don't have sudo, switch to root. If pip3 symlink does not exists, check for something like pip-3.X
Much python packages require also the dev package, so install it too:
sudo apt-get install python3-dev
Sources:
python installing packages with pip
Pip latest install
Check also Tobu's answer if you want an even more upgraded version of Python.
I want to add that using a virtual environment is usually the preferred way to develop a python application, so #felixyan answer is probably the best in an ideal world. But if you really want to install that package globally, or if need to test / use it frequently without activating a virtual environment, I suppose installing it as a global package is the way to go.
Well, on ubuntu 13.10/14.04, things are a little different.
Install
$ sudo apt-get install python3-pip
Install packages
$ sudo pip3 install packagename
NOT pip-3.3 install
The easiest way to install latest pip2/pip3 and corresponding packages:
curl https://bootstrap.pypa.io/get-pip.py | python2
pip2 install package-name
curl https://bootstrap.pypa.io/get-pip.py | python3
pip3 install package-name
Note: please run these commands as root
I had the same problem while trying to install pylab, and I have found this link
So what I have done to install pylab within Python 3 is:
python3 -m pip install SomePackage
It has worked properly, and as you can see in the link you can do this for every Python version you have, so I guess this solves your problem.
Old question, but none of the answers satisfies me. One of my systems is running Ubuntu 12.04 LTS and for some reason there's no package python3-pip or python-pip for Python 3. So here is what I've done (all commands were executed as root):
Install setuptools for Python3 in case you haven't.
apt-get install python3-setuptools
or
aptitude install python3-setuptools
With Python 2.4+ you can invoke easy_install with specific Python version by using python -m easy_install. So pip for Python 3 could be installed by:
python3 -m easy_install pip
That's it, you got pip for Python 3. Now just invoke pip with the specific version of Python to install package for Python 3. For example, with Python 3.2 installed on my system, I used:
pip-3.2 install [package]
If you have pip installed in both pythons, and both are in your path, just use:
$ pip-2.7 install PACKAGENAME
$ pip-3.2 install PACKAGENAME
References:
http://www.pip-installer.org/docs/pip/en/0.8.3/news.html#id4
https://github.com/pypa/pip/issues/200
This is a duplicate of question #2812520
If your system has python2 as default, use below command to install packages to python3
$ python3 -m pip install <package-name>
Easy enough:
sudo aptitude install python3-pip
pip-3.2 install --user pkg
If you want Python 3.3, which isn't the default as of Ubuntu 12.10:
sudo aptitude install python3-pip python3.3
python3.3 -m pip.runner install --user pkg
You can alternatively just run pip3 install packagename instead of pip,
Firstly, you need to install pip for the Python 3 installation that you want. Then you run that pip to install packages for that Python version.
Since you have both pip and python 3 in /usr/bin, I assume they are both installed with a package manager of some sort. That package manager should also have a Python 3 pip. That's the one you should install.
Felix' recommendation of virtualenv is a good one. If you are only testing, or you are doing development, then you shouldn't install the package in the system python. Using virtualenv, or even building your own Pythons for development, is better in those cases.
But if you actually do want to install this package in the system python, installing pip for Python 3 is the way to go.
Although the question relates to Ubuntu, let me contribute by saying that I'm on Mac and my python command defaults to Python 2.7.5. I have Python 3 as well, accessible via python3, so knowing the pip package origin, I just downloaded it and issued sudo python3 setup.py install against it and, surely enough, only Python 3 has now this module inside its site packages. Hope this helps a wandering Mac-stranger.
Execute the pip binary directly.
First locate the version of PIP you want.
jon-mint python3.3 # whereis ip
ip: /bin/ip /sbin/ip /usr/share/man/man8/ip.8.gz /usr/share/man/man7/ip.7.gz
Then execute.
jon-mint python3.3 # pip3.3 install pexpect
Downloading/unpacking pexpect
Downloading pexpect-3.2.tar.gz (131kB): 131kB downloaded
Running setup.py (path:/tmp/pip_build_root/pexpect/setup.py) egg_info for package pexpect
Installing collected packages: pexpect
Running setup.py install for pexpect
Successfully installed pexpect
Cleaning up...
You should install ALL dependencies:
sudo apt-get install build-essential python3-dev python3-setuptools python3-numpy python3-scipy libatlas-dev libatlas3gf-base
Install pip3(if you have installed, please look step 3):
sudo apt-get install python3-pip
Iinstall scikit-learn by pip3
pip3 install -U scikit-learn
Open your terminal and entry python3 environment, type import sklearn to check it.
To install pip for python3 use should use pip3 instead of pip.
To install python in ubuntu 18.08 bionic
before installing a version of python, activate virtual environment so that it won't have any problem in a future versions of python.
virtualenv -p /usr/bin/python3 py3env
source py3env/bin/activate
then install the actual python version you want.
>> sudo apt-get install python3.7
To install the required pip package in ubuntu
>> sudo apt-get install python3-pip
You Can Simply type in terminal/console .
Commands
sudo apt update
sudo apt upgrade
sudo apt install python3-pip3
pip3 install package-name
Another way to install python3 is using wget. Below are the steps for installation.
wget http://www.python.org/ftp/python/3.3.5/Python-3.3.5.tar.xz
tar xJf ./Python-3.3.5.tar.xz
cd ./Python-3.3.5
./configure --prefix=/opt/python3.3
make && sudo make install
Also,one can create an alias for the same using
echo 'alias py="/opt/python3.3/bin/python3.3"' >> ~/.bashrc
Now open a new terminal and type py and press Enter.