Monats-Archive: Januar 2015

Developing RPM packages for RHEL/CentOS with VirtualBox and Vagrant

TL;DR: Build and test RPM packages on local virtual CentOS machines before deploying to RHEL. We've recently delivered our first round of packages in a project where the customer is running Red Hat Enterprise Linux (RHEL). The default way of distributing software for RHEL and similar operating systems is by packaging it into an RPM…
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Introduction to the Titan graph database

This articles is the first articles in a series and introduces the Titan graph database as well as how to access it via the Gremlin console shell. Furthermore,  a basic schema for the ESecLog domain is introduced that is going to be used in future articles. Introduction In the last couple of years, graph databases have…
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Distances for Vehicle Routing with GraphHopper

This articles gives some hints for solving the Vehicle Routing with GraphHopper and OptaPlanner. It focuses on the GraphHopper's API to compute distances. I also recommend the blog post of Geoffrey De Smet about OptaPlanner and GraphHopper, that discusses the necessity of using real distances instead of euclidian distances for solving real vehicle routing problems.…
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