I recently updated from Python 3.5 to Python 3.6 and am trying to use packages that I had previously downloaded, but they are not working for the updated version of Python. When I try to use pip, I use the command "pip install selenium" and get the message "Requirement already satisfied: selenium in /Users/Jeff/anaconda/lib/python3.5/site-packages" How do I add packages to the new version of Python?
First, make sure that your packages do have compatibility with the version of Python you're looking to use.
Next, run pip freeze > requirements.txt in the base directory of your Python project. This puts everything in a readable file to re-install from. If you know of any packages that require a certain version that you'll want to re-install, put package==x.x.x (where package is the package name and x.x.x is the version number) in the list of packages to make sure it downloads the correct version.
Run pip uninstall -r requirements.txt -y to uninstall all packages. Afterwards, run pip install -r requirements.txt.
This allows you to keep packages at the correct version for the ones you assign a version number in requirements.txt, while upgrading all others.
I am wondering about this command pip install -r requirements.txt. Does pip install modules if they are not satisfied or does it try and install anyway even if the modules are already there? If it is the latter, than is there any way to write a shell script which checks if dependencies are satisfied and if not invoke pip install?
Pip only installs packages that are not installed yet.
This does mean that even if a new version is available, old packages will be kept. You can pass the --upgrade flag to prevent that behavior and install the latest versions (but then pip will call pypi for every package in your requirements file, in order to identify its latest version).
An alternative is to have version specifiers in your requirements file (e.g. mypackage==1.2.3), so that if you change your requirements file and use new versions, pip will pick those up without the --upgrade flag.
I was looking for a tutorial on how to install Python libraries in the wheel format.
It does not seem straightforward so I'd appreciate a simple step by step tutorial how to install the module named "requests" for CPython.
I downloaded it from: https://pypi.python.org/pypi/requests and now I have a .whl file. I've got Python 2.7 and 3.3 on Windows, so how do I install it so all the other Python scripts I run can use it?
You want to install a downloaded wheel (.whl) file on Python under Windows?
Install pip on your Python(s) on Windows (on Python 3.4+ it is already included)
Upgrade pip if necessary (on the command line)
pip install -U pip
Install a local wheel file using pip (on the command line)
pip install --no-index --find-links=LocalPathToWheelFile PackageName
Option --no-index tells pip to not look on pypi.python.org (which would fail for many packages if you have no compiler installed), --find-links then tells pip where to look for instead. PackageName is the name of the package (numpy, scipy, .. first part or whole of wheel file name). For more informations see the install options of pip.
You can execute these commands in the command prompt when switching to your Scripts folder of your Python installation.
Example:
cd C:\Python27\Scripts
pip install -U pip
pip install --no-index --find-links=LocalPathToWheelFile PackageName
Note: It can still be that the package does not install on Windows because it may contain C/C++ source files which need to be compiled. You would need then to make sure a compiler is installed. Often searching for alternative pre-compiled distributions is the fastest way out.
For example numpy-1.9.2+mkl-cp27-none-win_amd64.whl has PackageName numpy.
If you want to be relax for installing libraries for python.
You should using pip, that is python installer package.
To install pip:
Download ez_setup.py and then run:
python ez_setup.py
Then download get-pip.py and run:
python get-pip.py
upgrade installed setuptools by pip:
pip install setuptools --upgrade
If you got this error:
Wheel installs require setuptools >= 0.8 for dist-info support.
pip's wheel support requires setuptools >= 0.8 for dist-info support.
Add --no-use-wheel to above cmd:
pip install setuptools --no-use-wheel --upgrade
Now, you can install libraries for python, just by:
pip install library_name
For example:
pip install requests
Note that to install some library may they need to compile, so you need to have compiler.
On windows there is a site for Unofficial Windows Binaries for Python Extension Packages that have huge python packages and complied python packages for windows.
For example to install pip using this site, just download and install setuptools and pip installer from that.
To install wheel packages in python 2.7x:
Install python 2.7x (i would recommend python 2.78) - download the appropriate python binary for your version of windows . You can download python 2.78 at this site https://www.python.org/download/releases/2.7.8/
-I would recommend installing the graphical Tk module, and including python 2.78 in the windows path (environment variables) during installation.
Install get-pip.py and setuptools
Download the installer at
https://bootstrap.pypa.io/get-pip.py
Double click the above file to run it. It will install pip and setuptools [or update them, if you have an earlier version of either]
-Double click the above file and wait - it will open a black window and print will scroll across the screen as it downloads and installs [or updates] pip and setuptools --->when it finishes the window will close.
Open an elevated command prompt - click on windows start icon, enter cmd in the search field (but do not press enter), then press ctrl+shift+. Click 'yes' when the uac box appears.
A-type
cd c:\python27\scripts
[or cd \scripts ]
B-type
pip install -u
Eg to install pyside, type pip install -u pyside
Wait - it will state 'downloading PySide or -->it will download and install the appropriate version of the python package [the one that corresponds to your version of python and windows.]
Note - if you have downloaded the .whl file and saved it locally on your hard drive, type in
pip install --no-index --find-links=localpathtowheelfile packagename
**to install a previously downloaded wheel package you need to type in the following command
pip install --no-index --find-links=localpathtowheelfile packagename
Have you checked this http://docs.python.org/2/install/ ?
First you have to install the module
$ pip install requests
Then, before using it you must import it from your program.
from requests import requests
Note that your modules must be in the same directory.
Then you can use it.
For this part you have to check for the documentation.
Install distribute by downloading and running distribute_setup.py. This will make easy_install available, and from there you can install pip with easy_install pip. Then you can run pip install CAGE. Using pip to install things is a lot easier than messing with manually running setup.py, because pip can do things like:
automatically resolve dependencies
show you a list of all installed packages and their versions
install a set of specified packages from a requirements.txt
upgrade and uninstall packages
work with virtualenv
If you're on Windows, the one downside of pip occurs when there are C library dependencies, as pip will want a C toolchain installed so it can compile things. If that is the case, then there are two options. If there are precompiled binaries on PyPI, then just run easy_install package instead; easy_install knows how to use binary packages. You can also check Christoph Gohlke's site for executable installers of many binary packages. These can also be installed by easy_install if you want to use them with a virtualenv (just point it to the path of the .exe) or you can click and run if you don't care about virtualenv.
The main point is that no matter what route you choose to install packages, at no point are you ever moving around files by hand. You need to get out of the mindset of "I extracted this archive, where do I put these .py files?" That's not how it works. You're either running pip, running easy_install, running setup.py, clicking on an installer package, or using your distribution's installer. At no point are you ever doing anything by hand with the files directly.
Once you have a library downloaded you can execute this from the MS-DOS command box:
python setup.py install
The setup.py is located inside every library main folder.
For windows, there are automatic installer packages available at this site
It includes most of the python packages.
But the best way for it is of course using pip.
You don't need to download exclusively from the website. Just make sure you have pip (which you probably will if you have python installed). Just open your Command Prompt (CMD) and run the command:
pip install pygame
It will automatically download the correct whl version of pygame compatible with your configuration of PC. Make sure you remember the version which appears while "downloading" as this is the compatible version of .whl packages you shall be looking for in the future.
Simple steps to install python in Ubuntu:
Download Python
$ cd /usr/src
$ wget https://www.python.org/ftp/python/3.6.0/Python-3.6.0.tgz
Extract the downloaded package
$ sudo tar xzf Python-3.6.0.tgz
Compile Python source
$ cd Python-3.6.0
$ sudo ./configure
$ sudo make altinstall
Note make altinstall is used to prevent replacing the default python binary file /usr/bin/python.
check the python version
# python3.6 -V
i have write the answer here
How to add/use libraries in Python (3.5.1)
but no problem will rewrite it again
if u have or you can create a file requirements.txt which contains the libraries that you want to install for ex:
numpy==1.14.2
Pillow==5.1.0
You gonna situate in your folder which contains that requirements.txt in my case the path to my project is
C:\Users\LE\Desktop\Projet2_Sig_Exo3\exo 3\k-means
now just type
python -m pip install -r ./requirements.txt
and all the libararies that you want gonna install
C:\Users\LE\Desktop\Projet2_Sig_Exo3\exo 3\k-means>python -m pip install -r ./requirements.txt
I have a long requirements.txt and my network environment is not stable. Using pip install -r pip_requirements.txt will never make a successful install. Because if the connection is lost during the install and after I restart the install process, pip will download these packages from the beginning again. It would not use these packages that have been downloaded.
How can I make pip install package one by one rather than install after it have successfully downloaded all of the packages?
Try the option
pip install --download-cache="/folder/"
It will allow you to save the files to a local folder for later use.
You can also use
pip install --download="/folder/"
to just download and not install.
I am going through the Learn Python the Hard Way, 2nd Edition book, and I am stuck on this problem: "Use your setup.py to install your own module and make sure it works, then use pip to uninstall it."
If I type
setup.py install
in the command line, I can install the module.
But when I type
pip uninstall setup.py
it says:
Cannot uninstall requirement setup.py, not installed
The pip package index says, http://pypi.python.org/pypi/pip, says:
pip is able to uninstall most installed packages with pip uninstall package-name.
Known exceptions include pure-distutils packages installed with python setup.py install >(such packages leave behind no metadata allowing determination of what files were >installed)
Is there another way to install my module that pip will recognize?
By the way, I'm using a windows computer. Just wanted to mention that in case there are different solutions for Windows, Linux, and Mac.
You're giving pip a Python file and not a package name, so it doesn't know what to do. If you want pip to remove it, try providing the name of the package this setup.py file is actually part of.
There are some good suggestions in this related thread:
python setup.py uninstall