kristjan.rovsek

kristjan.rovsek

Genetic Algorithms in Elixir: Using reinsertions (source code)

Provided source code has some problems when dealing with the reinsertions.

  1. scripts/schedule.exs example has a default reinsertion strategy set to “elitist”. The problem is, it actually doesn’t and is always running the default “pure” strategy because the naming of the optional parameter has a typo. Changing “reinserton_strategy” to “reinsertion_strategy” does the trick.
  2. If we run the script again, correct strategy is used, but now we get an “ArgumentError” in “Toolbox.Reinsertion.elitist” function when trying to sort data based on fitness.
    The problem actually lies in the “Genetic.evolve” function. In it, “select” function is called which returns “parents” ( composed of pairs of chromosomes, ie: [{p1, p2}, {p3, p4}, …] ) and “leftovers” ( represented as a normal list of chromosomes, ie: [l1, l2, l3, …] ). These two get recombined in the
    “Toolbox.Reinsertion.elitist” function producing a list like [{p1, p2}, {p3, p4}, l5, l6] which is of wrong format.
    A solution then is to de-chunk the “parents” list before sending it to reinsertion function. Something like the following should do the trick:
      parents = parents
        |> Enum.reduce([],
          fn {p1, p2}, acc ->
            [p1, p2 | acc]
          end)
  1. While testing this I also found that the “population_size” parameter is not working. This is because “Genetic.run” does not pass optional parameters to function “Genetic.initialize”. Changing the call to:
population = initialize(&problem.genotype/0, opts)

solves it.

Where Next?

Popular Pragmatic Bookshelf topics Top

iPaul
page 37 ANTLRInputStream input = new ANTLRInputStream(is); as of ANTLR 4 .8 should be: CharStream stream = CharStreams.fromStream(i...
New
mikecargal
Title: Hands-On Rust (Chap 8 (Adding a Heads Up Display) It looks like ​.with_simple_console_no_bg​(SCREEN_WIDTH*2, SCREEN_HEIGHT*2...
New
New
jskubick
I think I might have found a problem involving SwitchCompat, thumbTint, and trackTint. As entered, the SwitchCompat changes color to hol...
New
nicoatridge
Hi, I have just acquired Michael Fazio’s “Kotlin and Android Development” to learn about game programming for Android. I have a game in p...
New
brunogirin
When I run the coverage example to report on missing lines, I get: pytest --cov=cards --report=term-missing ch7 ERROR: usage: pytest [op...
New
Charles
In general, the book isn’t yet updated for Phoenix version 1.6. On page 18 of the book, the authors indicate that an auto generated of ro...
New
adamwoolhether
Is there any place where we can discuss the solutions to some of the exercises? I can figure most of them out, but am having trouble with...
New
taguniversalmachine
It seems the second code snippet is missing the code to set the current_user: current_user: Accounts.get_user_by_session_token(session["...
New
Keton
When running the program in chapter 8, “Implementing Combat”, the printout Health before attack was never printed so I assumed something ...
New

Other popular topics Top

PragmaticBookshelf
Learn from the award-winning programming series that inspired the Elixir language, and go on a step-by-step journey through the most impo...
New
AstonJ
Or looking forward to? :nerd_face:
498 13326 269
New
Rainer
My first contact with Erlang was about 2 years ago when I used RabbitMQ, which is written in Erlang, for my job. This made me curious and...
New
AstonJ
I have seen the keycaps I want - they are due for a group-buy this week but won’t be delivered until October next year!!! :rofl: The Ser...
New
dimitarvp
Small essay with thoughts on macOS vs. Linux: I know @Exadra37 is just waiting around the corner to scream at me “I TOLD YOU SO!!!” but I...
New
AstonJ
Saw this on TikTok of all places! :lol: Anyone heard of them before? Lite:
New
AstonJ
If you get Can't find emacs in your PATH when trying to install Doom Emacs on your Mac you… just… need to install Emacs first! :lol: bre...
New
AstonJ
Was just curious to see if any were around, found this one: I got 51/100: Not sure if it was meant to buy I am sure at times the b...
New
New
AstonJ
Curious what kind of results others are getting, I think actually prefer the 7B model to the 32B model, not only is it faster but the qua...
New

Sub Categories: