Peterbe.com

If you're on the python-uk mailing list you will have already seen this but if you're not, here we go.

Fry-IT is hosting a Code Dojo in our offices. It's free and open to anyone. My colleague Nicholas has written up a little bit about what a Code Dojo is which should get you excited.

Details are available on this page which is also the place to go to secure your place. Currently there are 12 people who say they're coming and we've decided to cap the geek influx to 30 people.

Cheers,
Peter-san

A very sweet result to the Alan Turing petition ("Petition to: apologize for the prosecution of Alan Turing that led to his untimely death.").

It goes to show that there is hope for undoing wrongs in the past. Great work John!

If you met someone from Nestle, Pfizer, Wal-Mart, ExxonMobil, Chevron, Dow Chemical or Monsanto in a suit and who is proud of her job, would you punch her in the face? No? But would you pretend that you don't know about the ways of her company?

Eco blogger Eco-Chick has written a great write-up on some of the worlds greediest and least irresponsible companies. A great read if you're one of the millions of people who understand that corporate ownership of the world is a bad thing but don't necessarily know any specific details or examples.

When you're desperate for money you can do crazy things like rob a bank or mug an innocent old lady. But decisions to mug an old lady is 100% yours whereas office workers for irresponsible corporations are usually just a cog in a wheel, and therefore they all blame their destructive practices aren't their own idea or initiative. That is was someone "in upper management who decided". Would you dare to confront those excuses at a dinner party if you met one?

Hard-to-explain-type-of-online-art

I have a query that looks like this (simplified for the sake of brevity):

SELECT
  gl.id,
  miles_between_lat_long(46.519582, 6.632121,
                         gl.latitude::numeric, gl.longitude::numeric
                        ) AS distance
FROM 
 kungfuperson gl
 miles_between_lat_long(46.519582, 6.632121,
                        gl.latitude::numeric, gl.longitude::numeric
                        ) < 5000

ORDER BY distance ASC;

It basically finds other entries in a table (which has columns for latitude and longitude) but only returns those that are within a certain distance (from a known latitude/longitude point). Running this query on my small table takes about 7 milliseconds. (I used EXPLAIN ANALYZE)

So I thought, how about if I wrap it in a sub-select so that the function miles_between_lat_long() is only used once per row. Surely that would make it a lot faster. I accept that it wouldn't be twice as fast because wrapping it in a sub-select would also add some extra computation. Here's the "improved" version:

SELECT * FROM (
SELECT
  gl.id,
  miles_between_lat_long(46.519582, 6.632121,
                         gl.latitude::numeric, gl.longitude::numeric
                        ) AS distance
FROM 
 kungfuperson gl
) AS ss
WHERE ss.distance < 5000
ORDER BY ss.distance ASC;

To test it I wrote a little script that randomly runs these two versions many many times (about 50 times) each and then compare the averages.

Here I'm going to explain a solution I had to make for a site I recently launched. Basically, I wanted to cache the whole page in memcache and set the appropriate Expires and Cache-Control headers so that my view was only rendered once an hour and parts of the page needs to be unique (i.e. "Hi, logged in as xxxx")

The advantages is great: The page loads fast, content is stored in memcache every hour, page still appears to be dynamic.

The disadvantages are not so great: the AJAX loads fast but causes a flicker

Basically, I wrote a custom decorator called custom_cache_page(<delay in seconds>) that works like the normal cache_page(<delay in seconds>) decorator available in stock Django. However, my decorator inserts a piece of HTML into the rendered HTML (before it's stored in memcache) that I later use to update certain elements of the page with AJAX instead of server side.

Really impressed by the menu/nav on this e-commerce site. Couldn't be any more obvious how to find the teas you're looking for.

"A table of countries lists every country and whether they drive on the left side of the road or the right side of the road."

"SEO is not about creating a website sausage overstuffed with key words and phrases. It’s all about creating relevant and compelling content that transforms you into a thought leader who can become a trusted provider That is ultimately how you convert visitors into buyers"

Tonight we're launching our new Kung Fu website: kungfupeople.com

My friend Chris and I have been busy building a website where people who do kung fu can put themselves on a map to say where they train kung fu, what style they do and what kung fu club they belong to. The site is very much centred on having a world map and each little pin on the map is one kung fu martial artist.

This site is build in Django and is based on work that was done to build Django People originally developed by Simon Willison. We took his original code and revamped it almost completely.

Our goal is to slowly build up a world map of people from all sorts of clubs and styles and hopefully one day become the best place on the Internet for understanding what clubs are available where and what styles different people do. The site has been in an "alpha testing" phase now for a couple of weeks and even though we still have lots of ideas and cool features to add we believe it's ready to go live.

So if you train kung fu or know someone who trains kung fu go to our website and add yourself to the map