This post shows a simple implementation using R to solve a given TSP (Traveling Salesperson Problem) instance using the Pilot Method. The whole R script can be accessed here on my gist. How does the Pilot Method work? The Pilot Method is a construction heuristic to build (i.e. initial) solutions. The method tries to avoid… Read more Solve TSP using Pilot Method

## Minimal Git Knwo-How

This post is for people, who once in a while have to deal with git and therefore don’t repeat the commands frequently enough in order to keep them in longtime memory. ðŸ˜› I’ll provide a simple short reference containing the commands needed most frequently and enrich the reference when necessary. Clone an existing Repository from… Read more Minimal Git Knwo-How

## Calling GUROBI from Matlab

In this post I’ll show you the steps you need to take, if you want to use the powerful GUROBI solver from Matlab in order to solve Mixed Integer Linear Programs. Install the GUROBI Solver Go to the Gurobi website, create an account and download the version applicable for your operating system here. Acquire and… Read more Calling GUROBI from Matlab

## Solve Optimization Tasks using GUROBI Cloud

What is the objective here? I will document the steps needed to setup Gurobi to solve a Linear Program in the cloud. For this example we will use a simple linear model and use Matlab to invoke the locally installed Gurobi solver, which in turn would forward it to a Gurobi Compute Server, which we… Read more Solve Optimization Tasks using GUROBI Cloud

## How to Solve Linear Models in Matlab using GUROBI

There are situations where you might want to use a specific Mathematical Programming solver and you might have to transform the mathematical model to comply with the API specifications of that Solver. Here I want to show you, how to adapt a Linear Model in order to run it within Matlab using the Gurobi solver.… Read more How to Solve Linear Models in Matlab using GUROBI

## Run OSRM in Docker on Windows

After the OSRM routing service is no longer available on Windows we have a good reason to try to run it in a Docker container. However, there are some hurdles that have to be overcome in order to get your daemon up and running. SInce I’ve gone through this, I write down the necessary steps… Read more Run OSRM in Docker on Windows

## Set-Operations on data.frames

Have you been loooking for a nice way to determine differences of sets of dataframes in R? There is a very cool package, part of the tidyverse from Hadley Wickham. See here, how simple it is to perform this task in R, with dplyr installed: If you would like to preserve the information contained in… Read more Set-Operations on data.frames

## Change Local Library for R-Packages

You might have been wondering, that after having installed or updated your system to a new R version, the package installation Path within your RStudio still refers to your “old” location. In some situations, this might make sense. However, after changing to a completeley new version (main release number) of R, you might want to… Read more Change Local Library for R-Packages

## How to deal with black printing PDFs?

Let’s just quickly print out the PDF and go to bed. That was my initial plan. However, the task turned out to be significantly more difficult. I started the printing job and did some other stuff, until the job was done. Times where one had to sit next to the 9-needle printer connected to one’s… Read more How to deal with black printing PDFs?

## Marquee on a 8×8 LED Matrix Display run by a Battery powered Arduino Pro Mini

In this post I’ll show you how to implement a marquee running on an Arduino Pro Mini (5V). The project uses a slightly adapted version of the C source we developed for running the same project based on a Raspberry Pi 3B+. The main changes werd applied due to the two function void setup() and… Read more Marquee on a 8×8 LED Matrix Display run by a Battery powered Arduino Pro Mini