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

abtin
page 20: … protoc command… I had to additionally run the following go get commands in order to be able to compile protobuf code using go...
New
jesse050717
Title: Web Development with Clojure, Third Edition, pg 116 Hi - I just started chapter 5 and I am stuck on page 116 while trying to star...
New
herminiotorres
Hi @Margaret , On page VII the book tells us the example and snippets will be all using Elixir version 1.11 But on page 3 almost the en...
New
JohnS
I can’t setup the Rails source code. This happens in a working directory containing multiple (postgres) Rails apps. With: ruby-3.0.0 s...
New
jeremyhuiskamp
Title: Web Development with Clojure, Third Edition, vB17.0 (p9) The create table guestbook syntax suggested doesn’t seem to be accepted ...
New
adamwoolhether
When trying to generate the protobuf .go file, I receive this error: Unknown flag: --go_opt libprotoc 3.12.3 MacOS 11.3.1 Googling ...
New
curtosis
Running mix deps.get in the sensor_hub directory fails with the following error: ** (Mix) No SSH public keys found in ~/.ssh. An ssh aut...
New
brunogirin
When running tox for the first time, I got the following error: ERROR: InterpreterNotFound: python3.10 I realised that I was running ...
New
akraut
The markup used to display the uploaded image results in a Phoenix.LiveView.HTMLTokenizer.ParseError error. lib/pento_web/live/product_l...
New
mcpierce
@mfazio23 I’ve applied the changes from Chapter 5 of the book and everything builds correctly and runs. But, when I try to start a game,...
New

Other popular topics Top

siddhant3030
I’m thinking of buying a monitor that I can rotate to use as a vertical monitor? Also, I want to know if someone is using it for program...
New
brentjanderson
Bought the Moonlander mechanical keyboard. Cherry Brown MX switches. Arms and wrists have been hurting enough that it’s time I did someth...
New
PragmaticBookshelf
From finance to artificial intelligence, genetic algorithms are a powerful tool with a wide array of applications. But you don't need an ...
New
AstonJ
I’ve been hearing quite a lot of comments relating to the sound of a keyboard, with one of the most desirable of these called ‘thock’, he...
New
New
PragmaticBookshelf
Learn different ways of writing concurrent code in Elixir and increase your application's performance, without sacrificing scalability or...
New
rustkas
Intensively researching Erlang books and additional resources on it, I have found that the topic of using Regular Expressions is either c...
New
AstonJ
If you want a quick and easy way to block any website on your Mac using Little Snitch simply… File > New Rule: And select Deny, O...
New
husaindevelop
Inside our android webview app, we are trying to paste the copied content from another app eg (notes) using navigator.clipboard.readtext ...
New
sir.laksmana_wenk
I’m able to do the “artistic” part of game-development; character designing/modeling, music, environment modeling, etc. However, I don’t...
New

Sub Categories: