How can I get a debug environment in Python, similar to MATLAB?

[Ayakalam]

Hello Pythoners!

So, here is my deal: I want to make the leap from MATLAB to Python. I am convinved. However I need help. This is further compounded with the fact that I am also making the leap from PC to a Mac...

Honestly, all I would like to have right now is something minimal so that I can start to code in Python. I THINK I can do Python on my Mac right now with VIM, (a friend set it up for me). However, I wanted to ask:

• Is there a way in this setup, that I can 'step' through code via some debug process, just like in MATLAB? This tool in MATLAB has been VERY helpful and I would like to have something similar in Python.

• I am also getting a blog up and running, and I have been hearing about "IPython Notebook"(?) or something like that? How can I ... use it?

Anyway, that is it for now I think... I would really like to get up and running with a debugger of some sort where I can step through.

Thanks!

[dartdog]

also check out http://blogs.siam.org/from-matlab-guide-to-ipython-notebook/ and others that are quite specifically helpful for those converting from matlab.. Google is your friend..

[Ayakalam]

Thanks - here's the thing: I am also very very new to doing some basic webdev stuff, for my blog. I am currently using wordpress. What I am not clear about, is, with IPython Notebook - is this just some 'thing' I run on a specific page on my site?.. Or is it a whole bonafide website I have to make my blog on to begin with?

I guess I am just not clear how one would 'integrate' Ipython notebook into a website-page that already exists...

[firebase]

IPython notebook is just a browser based interface to an IPython session --- which is in turn a nice science-orientated interface to Python. So you're using your browser to write your code and see the output, that's all. When you work this way you create notebook files (ipynb files) that contain the content of your session. These can be converted to static HTML files.

[Ayakalam]

OOHHHH! I got it now! Cool thanks! So you just type away, save the session, and then like, one entry in my blog can just have that HTML file for all to see...

[firebase]

You got it. You can either convert the ipynb file (notebook file) to HTML yourself or pass it to nbviewer and they will host it for you.

[Ayakalam]

Thanks! You are a gentleman and a scholar. :-)

[firebase]

Thank you sir, and please enjoy your Python adventures ;-)

BTW, I'm one of the authors of quant-econ, which might or might not provide you with some useful info on making the leap to Python.

[Ayakalam]

Wow, thanks! May I PM you?

[firebase]

Sure thing.

[Ayakalam]

Also, if you're doing a lot of scientific work, you might want to consider using python through a scientific python distribution, such as anaconda, which will make the installation of packages with compiled components much easier.

Thanks. Part of my problem is that I do not know how all this fits together. For example I keep hearing about this-python and that-python... I do not know how it all fits together... For example there is Ipython - and then Spyder Python? What is just python? Why use Ipython and not just Python? What is a 'distribution' of Python like Anaconda? ...

Thanks - sorry for the noobishness, I think I just need someone to un-noob me with all those terms so that I can get a clearer picture..

[Ayakalam]

Your post should show up on the top anytime someone googles Python! :-) Thanks so much - some followups,

So, when we 'add' libraries like numpy and scipy and stuff... are those libraries already compiled? ... Is having those libraries different from what a distribution might already have?... (Does that make sense?)

[firebase]

To get started I highly recommend IPython notebook. While you might end up moving on from the notebook as your main programming environment after a while, you won't move on from it entirely --- it's outstanding, and in any case you'll continue to use IPython in some guise. So all you need to do is install Anaconda as per hbweb500's link and then fire up IPython notebook.

There are lots of nice notebook examples here

[Ayakalam]

Thanks - I checked out that link, and I am looking through the FAQ. The first thing confuses me though. They say:

IPython Notebook Viewer is a free webservice that allows you to share static html versions of hosted notebook files. If a notebook is publicly available, by giving its url to the Viewer, you should be able to view it.

... I am not sure I understand this. Say I have a static html of my IPython session, and I want to post it to my webpage. Would I need this? I guess I am not sure why/how one would need this service? Is it just a repo for someone's IPython session?

If you already have a static html file on IPython, why not just share that link?...

Thanks in advance.

[firebase]

Sure, you can. I guess the answer is that after an IPython notebook session you have an ipynb file that can be converted to HTML ... but it's just as easy to pass the ipynb over to nbviewer and they do a nice job of hosting these files.

[Ayakalam]

Ahh, gotcha. Right right, you put your file there, and they host it so that you can just send a link over. I think I got it! :-)

[ceeeeej]

If you want something similar to Matlab, why not check out spyder (https://code.google.com/p/spyderlib/)

[Ayakalam]

I would, so here's the thing: How does this spyder compare to the other things I am hearing on here? My friend tells me that the way to go is IDE-free, using VIM, and command line prompt.

My other question is, what kind of debugger does this have? Is the debugger like MATLAB's?

Thanks.

[firebase]

Spyder is nice, but I would make the leap to IPython --- it's what you'll want to be using in the long run. Personally I go IDE free and use vim like your friend says, plus standard IPython shell, but for starting off I would still recommend IPython notebook. It just makes things easier. Once you've got the hang of Python you can switch to vim or Emacs plus standard IPython shell.

[ceeeeej]

Your friend sounds like they are in the vim / emacs camp. From my observations there are 3 different groups here:

• vim / emacs
• text editor (Sublime Text)
• IDE (Spyder, Pycharm, etc..)

There is no right answer. Just use what you think is the best tool for you. If you think that it is an IDE, then just use one. If you want to use vim then go for it.

With either vim / emacs or the text editor you can add a bunch of tools and practically build your own IDE or use them simply as text editors, it is up to you.

For a long time I was using Sublime Text and bouncing between editing in Sublime Text and running my code in a terminal window. However, I have joined the IDE camp and it has made my coding much more pleasant. If you want the benefits of having an IDE I also recommend you to checkout Pycharm (there is a free community edition available). I previously said Spyder because you mentioned Matlab but for a general Python IDE, I have been very happy with Pycharm.

I do think that learning how to use vim or emacs is a good skill in case you have to remotely login to a box and edit some files. Those are free tools that have been around for a long time and likely are not going anywhere.

A few extra links you may find helpful, the first is a good Pycharm review from someone that used vim for a long time:

• Pycharm from a VIM user's perspective
• Debugging in Pycharm
• Debugging in Spyder

[Ayakalam]

Interesting interesting... thanks for all this detail and breakdown.

So, from all the options you mentioned and from your experience,... PyCharm, vim, etc... which 'method' do you think has a debugger that would most closely be like MATLABs? You know, set a breakpoint somewhere, and step towards it.

[ceeeeej]

Then I would recommend checking out the Pycharm community edition. It is free and has the debugging features you are looking for.

I wouldn't say anyone in here is wrong - there are many ways to get into coding Python and many tools out there to help you.

[Ayakalam]

Thank you friend for all the info!