Develop Reference

With Python 2.7.15 on a MAC console, virtualenv creates an environment with a different version of Python

Here is an extract of my console in a Mac, as you can see the Python on the console is 2.7.15 but on the environment it becomes 2.7.10 which is an older version... any help on why and how to fix it would be most welcomed!
dhcp-18-57:Wakeup6 **jbs$ python**
**Python 2.7.15** (default, May 1 2018, 16:44:14)
[GCC 4.2.1 Compatible Apple LLVM 8.0.0 (clang-800.0.42.1)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> exit()
dhcp-18-57:Wakeup6 jbs$ virtualenv env
New python executable in /Users/jbs/PycharmProjects/Wakeup6/env/bin/python
Installing setuptools, pip, wheel...done.
dhcp-18-57:Wakeup6 jbs$ source env/bin/activate
(env) dhcp-18-57:Wakeup6 **jbs$ python**
**Python 2.7.10** (default, Oct 23 2015, 19:19:21)
[GCC 4.2.1 Compatible Apple LLVM 7.0.0 (clang-700.0.59.5)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> exit()

If you installed python using Anaconda, then set up a new virtual environment for python 2.7.15 Then following directions in the Anaconda documentation, activate this virtual environment and you should be good to go.
If you didn't use Anaconda, just follow the directions for setting up a virtual environment on a Unix box. Then activate that environment and start working.
You can have multiple versions on your computer. Virtual environments allow you to run the version you want. I have virtual environments for python 2.7.13 and python 3.6.
If this doesn't work please let me know. I'll try to help.

Thank you all for your input. I finally figured out how to solve it. The difficult part was finding out how to locate the place where python 2.7.15 was installed which I'll leave intact in the response since I found it by trial and error looking in other places. I have not found a command that gives you the full path (perhaps an expert can tell us how to go from the laconic which python to the full path).
What I find interesting is that it does not really matter what the console uses when calling virtualenv. What matters is the version of Python used to install virtualenv which is the default version that will be used.
Essentially one has to use the -p option in virtualenv and make sure to find the right location where the desired version of python is.
dhcp-18--41:WakeUp8 jbs$ virtualenv -p /usr/local/Cellar/python#2/2.7.15/bin/python env
Running virtualenv with interpreter /usr/local/Cellar/python#2/2.7.15/bin/python
New python executable in /Users/jbs/PycharmProjects/WakeUp8/env/bin/python2.7
Also creating executable in /Users/jbs/PycharmProjects/WakeUp8/env/bin/python
Installing setuptools, pip, wheel...done.
dhcp-18-189-34-41:WakeUp8 jbs$ python
Python 2.7.15 (default, May 1 2018, 16:44:14)
[GCC 4.2.1 Compatible Apple LLVM 8.0.0 (clang-800.0.42.1)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> exit()
dhcp-18--41:WakeUp8 jbs$ pwd
/Users/jbs/PycharmProjects/WakeUp8
dhcp-18-189-34-41:WakeUp8 jbs$ source env/bin/activate
(env) dhcp-18-189-34-41:WakeUp8 jbs$ python
Python 2.7.15 (default, May 1 2018, 16:44:14)
[GCC 4.2.1 Compatible Apple LLVM 8.0.0 (clang-800.0.42.1)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>

Installing Scipy in Virtualenv

I've tried many ways to install scipy but without successes. I use virtualenv on Linux Mate.
After the workon command I tried
pip install scipy
or
easy_install scipy
end every time is a "failed with exit status 1"
I tried also
apt-get install python-scipy
and I've no errors but if I run python
python
import scipy
I'll have "ImportError: No module named scipy"
What is wrong?

I'd suggest using Miniconda to install scipy.
wget https://repo.continuum.io/miniconda/Miniconda-latest-Linux-x86_64.sh
bash Miniconda-latest-Linux-x86_64.sh -b
Then, create a Conda environment with scipy installed:
conda create -n scipy scipy
Now you'll have access to the activate and deactivate scripts, used to open and close Conda environments.
$ source activate scipy
discarding /Users/username/miniconda/bin from PATH
prepending /Users/username/miniconda/envs/scipy/bin to PATH
(scipy)$ python
Python 2.7.11 |Continuum Analytics, Inc.| (default, Dec 6 2015, 18:57:58)
[GCC 4.2.1 (Apple Inc. build 5577)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
Anaconda is brought to you by Continuum Analytics.
Please check out: http://continuum.io/thanks and https://anaconda.org
>>> import scipy
>>> scipy.version.version
'0.16.0'
[Edit] You indicated you want to use the system installed scipy package, that you have successfully installed via apt, in a virtualenv. You can instruct virtualenv to create a new environment that includes all the system Python packages like this:
$ virtualenv --system-site-packages scipy_env
New python executable in scipy_env/bin/python
Installing setuptools, pip...done.
$ source scipy_env/bin/activate
(scipy_env)$ python
Python 2.7.10 (default, Jul 14 2015, 19:46:27)
[GCC 4.2.1 Compatible Apple LLVM 6.0 (clang-600.0.39)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import scipy

Wrong Django version returned in virtualenv

I'm on a Mac running OS X !0.10 Yosemite. Default versions of Python & Django are 2.7 & 1.5. I'm want to set up a virtualenv that has Django 1.8 so I'm doing the following:
$ virtualenv --no-site-packages django18env
New python executable in django18env/bin/python2.7
Also creating executable in django18env/bin/python
Installing setuptools, pip...done.
$ source django18env/bin/activate
(django18env)$
Then I'm installing Django 1.8
(django18env)$ sudo pip install django==1.8
Password:
Downloading/unpacking django==1.8
Downloading Django-1.8-py2.py3-none-any.whl (6.2MB): 6.2MB downloaded
Installing collected packages: django
Successfully installed django
Cleaning up...
(django18env)$
Once that has run I have Django installed under django18env/lib/python2.7/site-packages/django
If I look at the __init__.py file in that directory it shows:
from django.utils.version import get_version
VERSION = (1, 8, 0, 'final', 0)
So it certainly looks like the right version is installed in the virtualenv directory. However, if I use django-admin --version I get:
(django18env)$ django-admin version
1.5.4
I've also tried starting python in the virtual env and getting the django version that way:
(django18env)$ python
Python 2.7.8 (default, Jul 29 2014, 21:50:48)
[GCC 4.2.1 Compatible Apple LLVM 5.1 (clang-503.0.40)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import django
>>> django.get_version()
'1.5.4'
>>>
Any ideas on why it still seems to be pointing to 1.5 when 1.8 is installed in the vertualenv?
I've read various other threads on here but can't get the version to point to 1.8
Any help much appreciated
Thanks

don't use sudo on virtualenv. the point of vitualenv is, to install software not system wide, but verily for that enviroment. but no matter inside a virtualenv or outside it, if you use sudo, it will install software to your system globally.
ziya#ziya:~/Desktop/coursera/python/lorem$ virtualenv ipsum
New python executable in ipsum/bin/python2.6
Also creating executable in ipsum/bin/python
Installing setuptools, pip...done.
#created a virtualenv
ziya#ziya:~/Desktop/coursera/python/lorem$ cd ipsum/
ziya#ziya:~/Desktop/coursera/python/lorem/ipsum$ . bin/activate
# will now install package with sudo
(ipsum)ziya#ziya:~/Desktop/coursera/python/lorem/ipsum$ sudo pip install sudokulib # i don't know what it is, just installing.
[sudo] password for ziya:
.....
Collecting sudokulib
/usr/local/lib/python2.7/dist-packages # attention to this path!
...
Successfully installed sudokulib-0.6a0
(ipsum)ziya#ziya:~/Desktop/coursera/python/lorem/ipsum$ python
Python 2.6.5 (r265:79063, Apr 16 2010, 13:57:41)
[GCC 4.4.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import sudokulib # import the newly installed module
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: No module named sudokulib
>>> exit()
(ipsum)ziya#ziya:~/Desktop/coursera/python/lorem/ipsum$ deactivate
#deactivating virtualenv and starting default python
ziya#ziya:~/Desktop/coursera/python/lorem/ipsum$ python
Python 2.7.3 (default, Dec 18 2014, 19:10:20)
[GCC 4.6.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import sudokulib
>>> sudokulib.__version__
'0.6a' #here it is!
>>> exit()
ziya#ziya:~/Desktop/coursera/python/lorem/ipsum$ . bin/activate
(ipsum)ziya#ziya:~/Desktop/coursera/python/lorem/ipsum$ pip install sudokulib #now installing the same module without sudo
Collecting sudokulib
Downloading sudokulib-0.6a.tar.gz
/home/ziya/Desktop/coursera/python/lorem/ipsum/lib/python2.6/site-packages
....
Successfully installed sudokulib-0.6a0
(ipsum)ziya#ziya:~/Desktop/coursera/python/lorem/ipsum$ python
Python 2.6.5 (r265:79063, Apr 16 2010, 13:57:41)
[GCC 4.4.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import sudokulib
>>> sudokulib.__version__
'0.6a' #seems ok now :)
>>>

I found the issue. As I say above, Django 1.8 was being installed in the virtualenv OK but Python wasn't using it. In the vitualenv I started Python and then:
>>>import django
>>>django.__file__
This showed that Django had been imported from:
/usr/local/Cellar/python/2.7.8/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages
And when I looked in my .bash_profile there was a line:
export PYTHONPATH=$PYTHONPATH:/usr/local/Cellar/python/2.7.8/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages
Not sure how/when this got in there but I commented it out, restarted the shell and I now get Django1.8 in my virtualenv and the older (default) version 1.5 outside the virtualenv.
Thanks for the help and suggestions

How to remove a module using Anaconda in Python

I have a package called 'Prody' which is installed under anaconda directories:
$ python
Python 2.7.8 |Anaconda 2.0.1 (x86_64)| (default, Jul 2 2014, 15:36:00)
[GCC 4.2.1 (Apple Inc. build 5577)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
Anaconda is brought to you by Continuum Analytics.
Please check out: http://continuum.io/thanks and https://binstar.org
>>> import prody
>>> prody.__file__
'//anaconda/lib/python2.7/site-packages/ProDy-1.5.1-py2.7-macosx-10.5-x86_64.egg/prody/__init__.pyc'
I'd like to remove that file with this command but failed:
$ conda remove prody
Error: no packages found to remove from environment: //anaconda
What's the right way to do it?

You can remove packages installed with pip using pip uninstall.

Did you install Prody via pip? Then I don't think that conda remove can remove it. AFAIK, conda manages only conda packages.

MacPorts on Snow Leopard: Python install seems to succeed but doesn't install a non-system Python

I've installed Python via MacPorts. According to this question, the files in /opt/local/bin should run the "correct" Python version. However, all those files are symlinks to:
/opt/local/Library/Frameworks/Python.framework/Versions/2.6/bin/
Running them directly from that folder (using no symlinks) runs an Apple build of Python!
Python 2.6.6 (r266:84292, Jan 6 2011, 13:25:25)
[GCC 4.2.1 (Apple Inc. build 5664)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>
For comparison, running /usr/bin/python shows a slightly different version:
Python 2.6.1 (r261:67515, Jun 24 2010, 21:47:49)
[GCC 4.2.1 (Apple Inc. build 5646)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>
They're both Apple builds! How do I install the correct version?

There are no "Apple builds" except the system Python (which is 2.6.1 on Snow Leopard, afai can deduce). The ports install seems to have worked as expected in this case. The reference to Apple is a reference to which GCC that was used.

I think it is running the build you want.
macports install every thing in /opt/local. So /opt/local/bin/python is a macport distribution.
/usr/bin/python is pre-install python distribution that comes with mac os x.
The following line, is an information about gcc build which is used for building macport python distribution.
[GCC 4.2.1 (Apple Inc. build 5664)]
If you have multiple versions of macport python installed, you can select the version using python-select
sudo port install python-select sudo
python-select python26
Also to ensure that you use macport python you could add the following to the PATH
export PATH=/opt/local/bin:$PATH