Thursday, 25 August 2016

Orienteering with Neo4j - moving from Cypher to the Dijkstra-APOC - part 1/2

So last July, my dear colleagues at Neo4j decided that they would tweet about a blogpost that I wrote 3 years ago.

The post was first published on my own blog over here, and then re-blogged over at the I also wrote a graphgist about it at the time, which I have revisited on the graphgist portal just now.

Some context

This entire thing started that summer with a blogpost by my friend and (at the time) colleague, Ian Robinson, about using a clever cypher query to calculate the weighted shortest path over a (small) graph. I decided to use that mechanism and apply it to my lovely hobby/sport: Orienteering. Pathfinding through forests, parks, cities - it's what we do in that sport, all the time. And efficient pathfinding in this environment, requires you to read the map, understand what the fastest route is, and run that as fast as you can. Effectively, when you want to "understand the fastest route", you will be weighing different alternative route choices against one another, and - as quickly as you can - choose that one for your run. It is, in effect, a total graph problem, a total "weighted shortest path problem" on a detailed map of your surroundings. So I used Ian's approach, and applied it to a small graph of an orienteering excercise in an Antwerp park.

Tuesday, 23 August 2016

Podcast Interview with Daniel Himmelstein, University of Pennsylvania

So today's podcast episode may well be one of the most interesting that I have ever published - and we have had some darn interesting episodes, if you ask me :) ... I got to know our guest, Daniel Himmelstein, by his great graphgist on "Drug repurposing by hetnet relationship prediction". Really interesting stuff - and Daniel actually got his PhD on this topic too. I found this video of his Thesis Seminar if you want more detail:

But for now we will just have a great conversation about his work. More interesting links below in the transcription - as usual.

Wednesday, 17 August 2016

Podcast interview with Stefan Plantikow, Neo Technology

Today's episode in the Graphistania podcast is one that I have really been looking forward to, for many reasons. First of all, our guest is such a lovely guy - feels like I could go out on a VERY long pub crawl with Stefan - seriously. Then, he has been working on some of the most interesting topics in Neo4j - another bonus. Most recently, he has worked on the "swiss army knife" of Neo4j tooling, the Awesome Apocs. Enough reason to have a good podcast chat together - and here that is:

Here's the transcript of our conversation from July 4th, 2016:
RVB: 00:02.518 Hello everyone, my name is Rik, Rik Van Bruggen from Neo, and here we are again, recording another Graphistania podcast, and today I have one of my lovely colleagues from the engineering team with me, Stefan Plantikow from Berlin. Hi Stefan.

Friday, 12 August 2016

The Great Olympian Graph - part 3/3

In part 1 of this blogpost series, we created and prepared a dataset with all the modern Olympian medallists from 1896 to 2012. In part 2, we loaded all that data into Neo4j: here's that article. Now, we of course want to do some interesting queries on the dataset, and see if the Graph will yield any interesting insights - as it usually does.

Easy querying - number of sports per Olympic game

Let's start with something easy - doing some counting of the numbers of sports in every game since 1896. Here's how we do that:
//number of sports per game 
match (y:Year)<--(e:Event)-->(d:Discipline)-->(s:Sport) 
with distinct as game, as sport 
return game, count(sport)order by game ASC
Then you can see that the number of sports has not really changed that dramatically over the years: In the early days we immediately went from 9 sports at the first Olympic game in 1896, to 19 in 1900.

Wednesday, 10 August 2016

The Great Olympian Graph - part 2/3

In the previous blogpost of this Olympic series I explained how I got to the dataset in 4 distinct .csv files that get generated from a 4-worksheet Google Spreadsheet. Here are the links to the 4 sheets:
Now, in order to load that data into Neo4j, I had to come up with a meaningful graph model.

Monday, 8 August 2016

The Great Olympian Graph - part 1/3

After my previous experiments with some sports data (most recently, the Tour de France 2016 results) in Neo4j, I recently saw the 2016 Olympic games coming up, and thought: well, there MUST be some interesting datasets to find around that - especially now that one of my favourite bike-riders in the world, Greg Van Avermaet, won the Gold Medal in the Cycling Road Race. Still so excited!!!

I did a bit of research and decided to settle on a combination of two datasets:
Just before the London Olympics in 2012,

Wednesday, 3 August 2016

Graphs @ Radiolab

So I go for my morning run the other day, and I put on my 2nd dearest podcast (after Graphistania, of course) - Radiolab. They have the most amazing stories that make me laugh, cry, read and research - and guess what: this episode is about GRAPHS!

Listen to this episode:
telling the amazing story of connectedness between soil, fungi, trees, and animals... aka the Wood Wide Web. The "internet of fungus", as the Beeb calls it.

Check out this TED talk too:
or this article about the "Intelligent Plant" and the connections that exist there.

If ever we needed more proof:


even on your daily podcast!