Archive for the ‘programming’ Category

Just 2 days left: Genetic Programming and Evolvable Machines anniversary issue available for free!

Thursday, July 29th, 2010

Cover of the journal of Genetic Programming and Evolvable Machines

A momentary interruption in the (slow) posting on the road trip (which has been done for nearly two weeks now!) to provide a time sensitive plug for those of you interested in genetic programming, evolutionary computation, and the like.

The Springer journal Genetic Programming and Evolvable Machines is celebrating its first 10 years with a special anniversary issue of articles reviewing the state of the field and considering some of its possible futures. For the month of July (which ends in two days!) the entire issue is available for free download.

Included in the issue are:

  • Human-competitive results produced by genetic programming
  • Theoretical results in genetic programming: the next ten years?
  • Genetic Programming and Evolvable Machines: ten years of reviews
  • Open issues in genetic programming
  • Grammar-based genetic programming: a survey
  • Developments in Cartesian Genetic Programming: self-modifying CGP
  • Bio-inspired artificial intelligence: theory, methods, and technologies

Once the month ends these will all start costing money again with two exceptions: the article on human-competitive results and the survey of 10 years of reviews will remain free in perpetuity.

In the spirit of full disclosure, I’m on the editorial board of the journal and contributed to one of the articles. Still, it’s a cool resource marking an interesting time in the development of the field, so take advantage of it while you can!

Flickr Uploadr is a pain, but Flickraw saved the day

Saturday, January 30th, 2010

Thomas McPhee as Arnold in the MAHS 2010 production of "The boys next door" as a one-act

Tom as Arnold in "The boys next door"


Flickr’s Uploadr is fine for small uploads, but tends to die consistently and unpleasantly when I have several hundred photos to upload, like those from Thursday’s opening of “The boys next door”, this year’s Morris Area High School one-act. It almost always takes me several tries to get a large pool of photos uploaded, which is a pain, but not fatal. This time, however, it chose to upload them in a semi-random order, so then it died I had 80-ish photos scattered all across the show, which meant I couldn’t just delete the first K from the list and restart the upload. Ugh.

Because it was late and I was in a hurry, I ended up just uploading the whole set (over several attempts), but marked them as private so people wouldn’t end up seeing two copies of that first group of images, figuring I’d sort things out in the morning.

The morning came, and it turned out that I really didn’t have a workable plan. All the pictures were on Flickr, but there was no good (i.e., automated) way to figure out which were the duplicates. If I could identify them, then deleting the duplicates and making the rest visible would be easy, but I didn’t have a clue how to find the duplicates using Flickr’s tools.

Sigh.

This would, however, be pretty straight forward in a script if I had all the data I needed, and this is where Flickr redeemed itself. They have a very rich API for accessing (and modifying) photos and their associated information (like tags), so if I could figure out how to use that I’d be golden. I’d poked a little with some Ruby Flickr libraries in the past, but none of them ever seemed very complete and they were always struggling to stay on top of Flickr’s changes and extensions to the API. A little searching this time, however, turned up Flickraw, which uses some really nifty Ruby metaprogramming to essentially build the Ruby part of the API “on the fly”, ensuring that it will be complete and up-to-date all automagically!

It turns out that Flickraw was indeed powerful, flexible, and easy to use. After authenticating (following the example on the Flickraw web site), I was able to use it to pull down a list of all the photos from “The boys next door”

my_owner_id = "68457656@N00"
play_title = "The boys next door"
my_stream = flickr.photos.search(
              :user_id => my_owner_id,
              :text => play_title,
              :per_page => 500)

I then split that list into the initial set of publicly visible photos, and the photos I’d uploaded after things got screwy and kept private (i.e., visible only to me):

public_photos = my_stream.find_all {|photo| photo.ispublic == 1}
private_photos = my_stream.find_all {|photo| photo.ispublic == 0}

My next task was to determine which of the private photos were duplicates of one of the public photos people were already looking at. All I really needed was the list of duplicates, but I decided to create lists of both the duplicates and the non-duplicates. I had to compare titles here because the Flickr IDs would be different; as far as Flickr knew they were all different photos. Happily, I had named them in a way that they each had a unique title, so if two photos had the same title, I knew they were the same shot uploaded twice.

dups = []
non_dups = []
private_photos.each do |photo|
  public_duplicate = public_photos.find { |pub| photo.title == pub.title }
  if public_duplicate
    dups.push(photo)
  else
    non_dups.push(photo)
  end
end

At this point, I could apply tags to all the photos in the two groups, and all the rest of the fiddling could be done through Flickr’s web tools:

non_dups.each do |photo|
  flickr.photos.addTags(:photo_id => photo.id,
                        :tags => "to_keep")
end

dups.each do |photo|
  flickr.photos.addTags(:photo_id => photo.id,
                        :tags => "to_delete")
end

I could have actually done everything with the Ruby script (delete the duplicates, change the remaining images to publicly visible, and add them to the appropriate set), but wanted to do that via Flickr so I could see what was happening as I went. And once the tags were in place, the work in Flickr was quite straightforward. The result: A set of 339 images that contains all the photos I uploaded, with no duplicates, all accomplished without deleting any of the original uploads.

Big thanks to Maël Clérambault, the author of Flickraw, for his excellent little library, and thanks to Flickr for providing this very nice set of API calls. (Now go fix Flickr Uploadr, damnit!)

As for the play – I just heard that they took second at today’s sub-sections competiton, which means they move on to sections next week, and Tom got a star performance award! Congratulations all!

I love our students (alumni edition)

Wednesday, December 2nd, 2009

_eli at MICS 2007

_eli at MICS 2007


These two tweets, each wonderful in their own way, just showed up back-to-back in my Twitter stream:

The joy of programming is taking a crappy piece of code, full of hacks and bad practices, and rewriting it to be better in every way. — LynnKale

for a moment I couldn’t think of a word for “thing to tell me how to do other things,” googled ‘how to’ and figured the word (documentation) — _eli

It’s gems like this that make my day. Both authors are UMM CSci alum, now off doing cool stuff. It’s neat to be able to stay in touch on-line.