kristjan.rovsek
Genetic Algorithms in Elixir: Using reinsertions (source code)
Provided source code has some problems when dealing with the reinsertions.
- 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.
- 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)
- 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.
Popular Pragmatic Bookshelf topics
In Chapter 3, the source for index introduces Config on page 31, followed by more code including tests; Config isn’t introduced until pag...
New
As per the title, thanks.
New
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
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
Modern Front-End Development for Rails - application does not start after run bin/setup (page xviii)
After some hassle, I was able to finally run bin/setup, now I have started the rails server but I get this error message right when I vis...
New
Modern front-end development for Rails, second edition - Struggling to get the first chapter to work
After running /bin/setup, the first error was: The foreman' command exists in these Ruby versions: That was easy to fix: gem install fore...
New
When running the program in chapter 8, “Implementing Combat”, the printout Health before attack was never printed so I assumed something ...
New
I got this error when executing the plot files on macOS Ventura 13.0.1 with Python 3.10.8 and matplotlib 3.6.1:
programming_ML/code/03_...
New
Getting an error when installing the dependencies at the start of this chapter:
could not compile dependency :exla, "mix compile" failed...
New
Is there any plan for volume 2? :slight_smile:
New
Other popular topics
Algorithms and data structures are much more than abstract concepts. Mastering them enables you to write code that runs faster and more e...
New
SpaceVim seems to be gaining in features and popularity and I just wondered how it compares with SpaceMacs in 2020 - anyone have any thou...
New
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
Learn different ways of writing concurrent code in Elixir and increase your application's performance, without sacrificing scalability or...
New
Continuing the discussion from Thinking about learning Crystal, let’s discuss - I was wondering which languages don’t GC - maybe we can c...
New
Use WebRTC to build web applications that stream media and data in real time directly from one user to another, all in the browser.
...
New
Inside our android webview app, we are trying to paste the copied content from another app eg (notes) using navigator.clipboard.readtext ...
New
Hello,
I’m a beginner in Android development and I’m facing an issue with my project setup. In my build.gradle.kts file, I have the foll...
New
Fight complexity and reclaim the original spirit of agility by learning to simplify how you develop software. The result: a more humane a...
New
Ok, well here are some thoughts and opinions on some of the ergonomic keyboards I have, I guess like mini review of each that I use enoug...
New
Categories:
Sub Categories:
Popular Portals
- /elixir
- /rust
- /ruby
- /wasm
- /erlang
- /phoenix
- /keyboards
- /python
- /js
- /rails
- /security
- /go
- /swift
- /vim
- /clojure
- /haskell
- /java
- /emacs
- /svelte
- /onivim
- /typescript
- /kotlin
- /c-plus-plus
- /crystal
- /tailwind
- /react
- /gleam
- /ocaml
- /flutter
- /elm
- /vscode
- /ash
- /html
- /opensuse
- /zig
- /centos
- /deepseek
- /php
- /scala
- /react-native
- /textmate
- /lisp
- /sublime-text
- /debian
- /nixos
- /agda
- /django
- /kubuntu
- /arch-linux
- /deno
- /nodejs
- /revery
- /ubuntu
- /manjaro
- /spring
- /diversity
- /lua
- /markdown
- /julia
- /c








