Have your own basic OsmAnd map
Ever wondered how to create your own map and see it on your website or on an App like OsmAnd? Look no further and let me help you through the process of creating your own tile server.
OpenSourcES
OpenSourcES: is a blog about coding things from scratch.
Latest posts
Graphs.jl: The Myers difference algorithm
A Julia implementation of the Myers difference algorithm
TSPSolver.jl: 2-opt
Using 2-opt to find a better upper bound
TSPSolver.jl: Using Bonobo.jl to solve our first instance
Solving our first real TSP problem using Bonobo.jl as a branch and bound framework.
Lessons Learned: A Julia Project Recap
How I structured my ConstraintSolver.jl package and what I learned in two and a half years of working on it. Bad approaches and good ones.
Javis: Taxi Trip Visualization
Visualizing taxi trips in Porto, Portugal using Javis and various other Julia packages.
Bonobo.jl: Branch and Bound
The start of a general branch and bound framework for mathematical optimization problems in Julia.
TSP: Greedy approach and using a 1-Tree
An introduction to the most simple TSP heuristic as well as a more sophisticated lower bound. More coming soon
About me
About me, Ole Kröger and OpenSourc.ES
Matrix multiplication: Performance
A deep dive into the performance we can obtain by thinking about cache lines and parallel code. An example step by step guide on optimizing dense matrix multiplication.
Javis.jl examples series: Collatz Conjecture
What is the Collatz conjecture and how can we visualize the tree that is underlying it? A visual exploration of the problem in Julia with animations using Javis.jl
Javis.jl examples series: Inverse Kinematics
How to reach an object using a robotic arm? With Inverse Kinematics. A visualization and explanation using Julia and the animation engine Javis.jl
Javis.jl examples series: The chase problem
Animating a simple problem in Javis. Exploring different ways of animating in the newer versions of Javis
Master thesis: HyperOrdering
Explaining the fast pseudocode behind HyperOrdering. A way to find a minimum degree node ordering.
Master thesis: Minimum degree ordering
How to permute a sparse system of linear equations such that a decomposition stays sparse? An introduction into minimum degree ordering.
First YouTube video created with Javis
How I created the first 7 minute video with the animation framework Javis.jl and what you can learn from it.
Ghess: How to write a Chess Engine?
How to write a chess engine. An introduction to ideas, testing and interesting bugs.
Benchmarking and Profiling Julia Code
Find out how to benchmark and profile your Julia code Find the spots that aren't as fast as expected to run with the speed.
Share what you've learned!
Share which tool, workflow, package helped you out with the rest of the community
Boolean constraints
Extending JuMP with boolean constraints for my ConstraintSolver.jl
Generic bridges
How to create generic bridges in JuMP?
Creating bridges with JuMP.jl and MOI.jl
How to create your own JuMP/MOI bridges?
Constraint Solver: Priority Queue
Using a priority queue to speed up get_next_node
Graph Coloring using Cliques
Using maximal cliques to find graph colorings faster.
Javis v0.3: How to animate a Fourier series
The biggest changes in Javis v0.3 and how it makes animations easier. Making Fourier animations in a few minutes.
Debugging in Julia - Two different ways
Different ways of debugging Julia code without using println. Some deep, some fast and fun.
The Julia Package Manager
How to use the package manager in Julia and create your own environment or package.
Javis v0.2 and the Future
What's new in Javis v0.2 and what have we planned for the future?
Javis.jl with Animations.jl
How to make powerful animations in JuliaLang with Javis.jl and Animations.jl?
Housekeeping August 2020
What happened in August? First version of Javis.jl. Project management, master thesis and the future.
ConstraintSolver.jl Refactoring
Refactoring of ConstraintSolver.jl and what I've learned about properties and hashes.
The beginning of Javis.jl
A small introduction to the new project Javis.jl. What do you want to animate?
Visualizing Pi, Tau and prime numbers
Visualizing Pi, Tau as well as prime numbers using Luxor.jl
ConstraintSolver.jl Reified constraint
How to extend JuMP to support a new constraint type? The reified constraint.
Pi vs Tau
Is Pi better or Tau? I'm always for pie. Mathematical reasons are boring. Your visual cortex should decide.
Side gig: Mentoring Julia newcomers
Why I think code reviews/mentoring are helpful for beginners. What do I have to offer?
Julia Basics: REPL & Revise
What do I need to start with Julia? Learning the REPL and Revise.
Julia Basics: Multiple Dispatch
Series of Julia basics: What is multiple dispatch? Explanation on how to use it and why it is powerful.
ConstraintSolver.jl Indicator Part 2
Extending JuMP.jl in your own package to support more constraints.
Franklin.jl
Using Franklin for the new blog layout. A static site generator written for Julians.
Indicator constraint + Benchmarks
Part 23: Adding an indicator constraint to the ConstraintSolver
Housekeeping May 2020
Housekeeping: Logo for the constraint solver, Exercism, Streaming and a new blog layout which hopefully comes soonish.
Bugs and Benchmarks
How to build a constraint programming solver in Julia. Part 22: Bugs, debugging and benchmarking without loosing sanity
Solving Str8ts
How to build a constraint programming solver in Julia. Part 21: How to solve Str8ts using constraint programming?
Table constraint
How to build a constraint programming solver in Julia. Part 20: Implementing the table constraint.
ConstraintSolver.jl v0.1.0
Final bits and pieces to release the first version of this project.
Bound computation
Computing reasonable bounds for the constraint solver for a dramatic speedup
COVID-19 Visualization
Creating a visualization of COVID-19 cases using public data and Luxor.jl
Table logging in Julia
Log something in a table by adding rows to the command line. Useful for things like solvers to show best bounds, incumbents and some other information
Building an Enigma emulator and a Bombe
How does the Enigma work and how to code one? As well as getting the flaws and crack the code