I was trying to install shogun on Windows:
http://www.shogun-toolbox.org/doc/installation.html
but evidently it requires python 2.5 to work. I tried with python 3 and it didn't work. But then python 2.5 no longer exists.
Does anybody know how to get it working with python without using python 2.5?
You won't get very far trying with Python 3 (which is not fully compatible with Python 2.x).
Furthermore, the installation instructions say:
"SHOGUN requires the standard linux
utils like bash, grep, test, sed, cut,
ldd, uname gcc g++ cat python"
sounds like you are out of luck on windows, unless you resort to Cygwin.
There are currently two Python languages out there
the original one, which is still being updated (currently at 2.7.2)
the overhauled Python 3, which is breaking compatibility (currently at 3.1.4)
Many libraries have not switched to Python 3 yet, and might not for some time, so you're better off getting 2.6 or 2.7.
For Windows or Mac, I can recommend the Enthought distribution (free for academic use), which contains loads of goodies, including scipy, which you'll very probably need -- and installs hassle-free!
Related
I have a project with Python 3.5.4, but I want to use a Python library called pyghmi, but the library only supports the Python 2.x.
How can I solve this issue?
The project was updated for python3 and is tested with python 3.5, though I will confess the vast majority of users are using python 2.7 at the moment. The building of rpms, however, has not yet been tested for python3 (so far system python of centos 6 and centos7 has been the rpm environment).
I would be interested to know the issue you are hitting.
I am not a regular Linux user so this might be completely trivial question. I am running 6.2 PUIAS version i386_64 on one of my GPU based "super" computers due to the unavailability of NVidia drivers for NetBSD. The installed version of Python is 2.6.6. I need 2.7.2 Python and newer version of scipy, numpy, matlibplot and friends. I have PUIAS and EPEL repositories enabled. However they do not have newer versions of Python. What is the "recommended" way to install newer version of Python without braking the system which depends on it. I am not interested in Python 3.2 due to the lack of libraries for scientific computing.
When the install-Python-from-source routine tells you to use make install, type make altinstall instead. This will leave the normal python executable untouched and instead create python2.7 for you to use. Install the other packages from source using this new executable. Don't forget to change the shebang line in your scripts accordingly.
I am going to answer my own question. For people who are using Python for scientific computing on RedHat clones (PUIAS for example) the easiest way to get all they need is to use rpm package manager and Enthought Python Distribution (EPD for short). EPD installs everything in a sandbox so system tools which are based on an obsolete version of Python are not massed up. However, paths have to be adjusted for system or even easier on the user base so that the using shell invokes non-system tools. One should never compile Python from source unless you are interesting in Python itself or in porting it to your favorite operating system rather than in your own research!
I'm a newbie programmer just installing Python 3.2, but I know I also have an older version of Python on my machine. in fact, I think Macbook comes with it installed. Do I have to worry about having different versions on my computer when I try to start learning Python?
For the most part, you don't have to worry about conflicts with system Python. In fact it is recommended to install a different Python version instead of working with system Python. Also consider using virtualenv and virtualenvwrapper to maintain any dependencies for each project easily without conflicts.
It really depends what OS you're talking about. I'm assuming you're talking about a Mac, since you mentioned Macbook.
Macs come with 2.5 and 2.6 installed as far as I'm aware. At least mine has both those versions, and I've only installed 2.7 manually.
You can check which version of python is the current 'system' python by doing the following in terminal:
// check the version of system python
python --version
// tells you where the system version of python is on your PATH
which python
On *nix type Operating Systems, like your Mac, applications aren't really 'installed', like they are in Windows (eliding details). Instead, application files are placed in various different parts of the file system. Python, for example, is placed into the following directory (by default) when installing 2.7:
/Library/Frameworks/Python.framework/Versions/2.7/bin/python
Since this directory isn't on the system PATH, this version of python won't be used when simply calling python from the command line. The system will search all the folders in the PATH environment variable for an executable file called python. It will usually find it in /usr/bin/ or something similar.
To make a new version of Python the 'system' python, you have a couple of options:
Modify your .bash_profile, and prepend the path to your new python to the PATH environment variable.
symlink the new version of python to a directory already on your PATH like /usr/bin/
Be aware that Mac python installers can modify your .bash_profile (in your home directory), to force the new version to be the default system version. This is what my bash_profile shows:
# Setting PATH for Python 2.7
# The orginal version is saved in .bash_profile.pysave
PATH="/Library/Frameworks/Python.framework/Versions/2.7/bin:${PATH}"
export PATH
You can happily run multiple versions of python on the same system. A particular version is usually the default though, and that's whatever executable python file is found on the PATH first.
If you want to use a different version at any particular point in time, you can:
/path/to/python/2.4/python some_script.py
/path/to/python/2.7/python some_script.py
/path/to/python/3.2/python some_script.py
That will execute the script some_script.py under 3 different versions of python. Of course, you need to make sure that the /path/to/python is correct.
So yes, you need to be mindful about what version of python you are going to be using, hopefully this will guide you into understanding how applications are installed and which version of an application is launched by default when you don't provide a path.
Yes, 3.x Python syntax is not backward-compatible with 2.x. So if you learn Python 3.x you might not be able to port your knowledge to Python 2.x.
Moreover you should choose if you want to learn 3.x or 2.x. 2.x is far more widespread than 3.x, but 3.x is where Python is heading. No more innovation will happen in 2.x, and in mid-term most frameworks will be ported to 3.x (right now there are some notable exceptions)
Hope that helps!
In general, you should be fine. Since the Mac is BSD-based, it should maintain the "python" command as pointing to the version that your system requires, which is usually an older version like 2.5. You may have to use a command like python3 to run your Python 3 programs, but other than that it should be transparent to you.
As you learn and become more advanced, you can begin using the virtualenv system to maintain separate Python installations for multiple projects.
Python version with different major or minor version numbers can be installed in parallel. For example, you can have 2.4, 2.5, 2.6, 2.7 and 3.1 on the same machine. However, you can't have versions with the same major and minor number installed at the same time (at least, not without tricks), so you can't have 2.5.2 and 2.5.4 at the same time.
Note that you will have to install any third-party libraries once for every Python version.
It is very well possible to have multiple versions of python on your machine. Just make sure, that if you call python in your console it uses the python you want it to use. Same goes for your IDE.
Regarding the version: It is always nice to have the latest version on board (in python however there are compatibility issues to take into account) , since there might be features you want to use, that are only available with a certain version and upwards. Since this is sometimes tricky to find out, especially if you are new to the field, going with the latest version might be how you should proceed.
Be careful before installing new version of python.
Python has no backward compatibility.
Scripts written for python 2.7.* won't work on python 3
For example,
print "Hello" will work on python 2.7 but not on version3
I have Python2.6.5 and Python2.4.4 on my linux machine.
At the moment, all the modules I have (wx, ply, pyserial, twisted, to name a few) are installed for the 2.6 version of python. If I try to import wx on Python2.4, I get the expected no module error.
The problem here, is that I have a lot of devices (Let's say over a thousand) all running 2.4.4, which will soon need to be supported by this machine (For builds of code, releases etc). Until now, I've been using an EeePC (Same device as the ones I'm supporting) to do builds and releases, which has worked well. (I develop on the 2.6 machine, and build on the EeePC).
How would I go about getting these modules to work for Python2.4? I've tried reinstalling (With 2.4 as my primary), but that just caused errors. The blogs/answers I've found say to use easy_install, but that doesn't support the packages I need (Or at least, it just died when I tried).
In short: I'm currently using python 2,6, but I'd like it to change to 2.4 for all the modules as that's what I'm going to be using.
You can't share modules between different versions of Python. If you want to use wxPython from Python 2.4, you need to install it for Python 2.4.
You said you tried to install it with Python 2.4 as your "primary". I'm not sure what that means. You would install wxPython for Python 2.4 by running the installer with Python 2.4, like so:
$sudo /usr/bin/python2.4 setup.py install
Or similar.
You can use easy_install as well, but then you need to install Distribute for Python 2.4 first. Did you do that?
I recently wrote a full explanation on my blog about this: http://regebro.wordpress.com/2011/02/02/newbie-hint-on-installing-python-and-its-modules-and-packages/
Don't attempt to share them; this has some chance of success with pure Python modules, but C modules will fail to work. Instead, install them using the appropriate interpreter executable, e.g. python2.4 setup.py install.
I'm currently toying with python at home and I'm planning to switch to python 3.1. The fact is that I have some scripts that use python 2.6 and I can't convert them since they use some modules that aren't available for python 3.1 atm. So I'm considering installing python 3.1 along with my python 2.6. I only found people on the internet that achieve that by compiling python from the source and use make altinstall instead of the classic make install. Anyway, I think compiling from the source is a bit complicated. I thought running two different versions of a program is easy on Linux (I run fedora 11 for the record). Any hint?
Thanks for reading.
On my Linux system (Ubuntu Jaunty), I have Python 2.5, 2.6 and 3.0 installed, just by installing the binary (deb) packages 'python2.5', 'python2.6' and 'python3.0' using apt-get. Perhaps Fedora packages them and names them as RPMs in a similar way.
I can run the one I need from the command line just by typing e.g. python2.6. So I can also specify the one I want at the top of my script by putting e.g.:
#!/usr/bin/python2.6
Download the python version you want to have as an alternative, untar it, and when you configure it, use --prefix=/my/alt/dir
Cheers
Nik
You're not supposed to need to run them together.
2.6 already has all of the 3.0 features. You can enable those features with from __future__ import statements.
It's much simpler run 2.6 (with some from __future__ import) until everything you need is in 3.x, then switch.
Why do you need to use make install at all? After having done make to compile python 3.x, just move the python folder somewhere, and create a symlink to the python executable in your ~/bin directory. Add that directory to your path if it isn't already, and you'll have a working python development version ready to be used. As long as the symlink itself is not named python (I've named mine py), you'll never experience any clashes.
An added benefit is that if you want to change to a new release of python 3.x, for example if you're following the beta releases, you simply download, compile and replace the folder with the new one.
It's slightly messy, but the messiness is confined to one directory, and I find it much more convenient than thinking about altinstalls and the like.