A website for LFPUG
Didrik Pinte has put together a web page on the Python.org Wiki for the London Financial Python Users Group. Only a little content so far, but it will grow... if you're doing financial work in Python in London, do come along to the next meeting -- it will be 7pm next Monday (14 December) at MWB Regent Street, Liberty House 222 Regent Street, London W1B 5TR. You may have to put up with me talking for a while about a spreadsheet you already know everything about, but there will be interesting bits too ;-)
New York Financial Users Group
A quick follow-up to my last post; the guys at Enthought are also starting a Financial Python Users Group for New York. If you're interested, the LinkedIn group is here.
London Financial Python Users Group
Last night, I went to the inaugural meeting of the London Financial Python Users Group. It was a small gathering (as you'd expect for a new group), just four of us, but a very interesting one. Didrik Pinte gave a presentation of an interesting new library called pandas, a useful layer on top of existing stats packages that provides some very neat data-alignment capabilities, and we also discussed what future meetings should involve (lightning talks are definitely on the cards).
As with all these things, the most interesting discussions were left for the pub afterwards. I was particularly interested in what Didrik had to say about Cython, a tool which lets you write CPython C extensions in Python (!). I'll have to play with it and see if it can easily integrate with Ironclad...
Anyway, the next meeting is very tentatively planned for 14 December; the best way to track the group is probably currently the LinkedIn group, though I will definitely also post the details when they firm up.
R in Resolver One (and perhaps IronPython generally)
We've just announced the winner of this month's round of our competition at Resolver Systems, and it's a great one; Marjan Ghahremani, a student at UC Davis, managed to work out how you can call R (a powerful statistical analysis language) from our spreadsheet product Resolver One. You can download a ZIP file with a detailed PDF describing how it works and a bunch of examples.
If you're not interested in Resolver One, but want to use R from your own IronPython scripts, you may be able to do that too, using her instructions as guidelines -- I've not tried it myself, but there are no obvious blockers. If you do try it out, I'd love to hear how it goes.
xmlrpc
One of our customers had been asking about how to call XMLRPC servers from
Resolver One. It doesn't work in version 1.3, and he was having problems getting
it to work in 1.4. The problem turned out to be simple and fixable, and unlikely
to affect other people, so I'm proud to present a really simple XMLRPC/Resolver One example
that you can use as a starting point: a Python script that creates a server
exposing an is_even function (which tells you if a number is even or not), and
a Resolver One spreadsheet that uses it. There are only two lines of code in
the spreadsheet, which is pretty cool :-)
Getting phpBB to accept Django sessions
phpBB is a fantastic bulletin board system. We use it at Resolver Systems for our forums, and it does a great job.
However, we're a Python shop, so we prefer to do our serious web development -- for example, the login system that allows our paying customers to download fully-featured unlocked versions of our software -- in Django.
We needed to have a single sign-on system for both parts of our website. Specifically, we wanted people to be able to log in using the Django authentication module, and then to be able to post on the forums without logging in again. This post is an overview of the code we used; I've had to extract it from various sources, so it might not be complete -- let me know in the comments if anything's missing.