Showing posts with label graph algorithms. Show all posts
Showing posts with label graph algorithms. Show all posts

Monday, 29 March 2021

Part 3/3 - Wikipedia Clickstream analysis with Neo4j - some Graph Data Science & Graph Exploration

In the previous blogposts, I have tried to show
  • How easy it is to import the Wikipedia Clickstream data into Neo4j. You can find that post over here.
  • How you can start doing some interesting querying on that data, with some very simple but powerful Cypher querying. You can find that post over here.
In this final blogpost I want to try to add two more things to the mix. First, I want to see if I can do some useful "Graph Data Science" on this dataset. I will be using the Neo4j Graph Data Science Library for this, as well as the Neuler Graph App that plugs into the Neo4j Desktop. Next, I will be exposing some of the results of these Graph Data Science calculations in Neo4j's interactive graph exploration tool, Neo4j Bloom. So let's do that. 

Installing/Running the Graph Data Science Library

Thanks to Neo4j's plugin architecture, and the Neo4j Desktop tool around that, it is now super easy to install and run the Graph Data Science Libary - it installs in a few clicks and that you are off to the races:

Tuesday, 26 February 2019

Podcast Interview with Amy Hodler, Neo4j

Yes! Another great interview for our podcast, this time with a great colleague of mine who has a big mind and many ideas around one of the most fascinating and under-used topics evah: Graph Algorithms and Artificial Intelligence. Amy Hodler has a lot to say on this topic, and is about to publish a fantastic new book on the topic together with Mark Needham. I think you will enjoy this one - even though it's a bit longer than usual. Here goes:


Here's the transcript of our conversation:
RVB:  00:00:00.938 Hello, everyone. My name is Rik, Rik Van Bruggen from Neo4j, and here we are again, recording another episode of our Graphistania Graph Database Podcast. And tonight I have a dear colleague of mine on the other side of this Google call, and that's Amy Hodler. Amy, how are you?

Monday, 29 August 2016

Orienteering with Neo4j - solving the 1000-control race with the Dijkstra-APOC - part 2/2

In part 1 of this blogpost, I explained how you can use the Awesome Neo4j APOCs to calculate a weighted shortest path on a graph with a more optimized and more efficient algorithm, based on Dijkstra's work. In this second and last blogpost on this topic, I would love to explain a bit why I think this is pretty much a very big deal. APOCs give you access, from Cypher, to a whole slew of graph algorithms, many of them very useful for all kinds of different graph operations.

Orienteering - a bit more complicated in the real world

One reason why I wanted to write this second post, is of course because my lovely sport - Orienteering - is of course a bit more complicated in the real world than what you have seen in that little park run that I talked about in the previous two posts. To give you a feel for it:

  • Here's an excerpt of my run in the World Masters Orienteering Champs a few weeks back in Estonia. More details over here - but I can tell you that for each and every one of these legs there's at least half a dozen different route options - and of course my course had 20+ control points too. So a bit more of a bigger graph anyway!
  • And here's another example: actually being run today (August 25th) is the actual elite's World Orienteering Champs on the long distance. Just. Look. At. This. Map.

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 neo4j.com/blog. 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.

Wednesday, 20 July 2016

Graphing the Tour de France - part 3/3

In the past two blogposts I have been creating and importing some nice Tour de France 2016 data. It's a small dataset, for sure, and this is by no means a realistic graph application - but perhaps we can still have some fun exploiting the data with some cypher queries. That's what we'll try now. I have put all of the example queries together in this gist, so please feel free to play around with it :) ... let's take you through it.

Is the model really there?

First and foremost, let's verify the model that we wanted to put in place, with yet another AAPOC (Awesome APOC). We thought we were going to get this model: