• ### I almost bumped into a friend on the Hochschwab

July 28, 2022

On a weekend in July 2022, a couple of friends and I decided to go for a hike in the Hochschwab mountains in Austria. When I posted the photos a couple of days later, another friend commented that she, too, had been there during the weekend. Did we just miss each other by a couple of minutes, or were we much farther apart? I looked our track logs to find out.

• ### I reached a dead end in my research about road numbers (but this didn't stop me from making a cool map and finding some interesting insights)

February 7, 2022

On May 7, 2022 a Hungarian version of this article has been published on Qubit.hu, a Hungarian popular science website.

I have been wondering for some time about the system behind the numbering of roads in Hungary. The system itself is simple: the main road that leads from Budapest to Vienna is number 1, the other main roads radiating out from the capital are numbered in clockwise sequential order. Connecting roads have two (or sometimes three) digits. But why is this the system? How long has it been like this? What happened when the borders of the country changed?

• ### Why did I get to drive this car for €0.01 per kilometer?

April 13, 2021

I’m not sure but I have an idea.

• ### A couple of lines of Python for a night of family fun

March 9, 2021

Have you ever wondered what words you can spell out using wooden cubes that have letters on each face? I have.

February 24, 2021

If you enjoy geocaching, you might want to go paperless and just bring a smartphone or GPS device with you on your treasure hunt. Alternatively, you might want to have a backup with you on paper if anything goes wrong with your device. I wrote a simple web service that helps you with the second case.

• ### Is there enough space in Manhattan to stay six feet apart?

October 17, 2020

According to my analysis, it is likely that there is, but this seems not to be the case in other, more densely populated localities.

• ### Graphing Construction on Tram Line 6 in Budapest

June 30, 2020

In this article I explore a method to visualize linear spatial data that changes over time: which segments of tram line 6 of Budapest were under construction at which points in time? This investigation is inspired by a video posted on Index.hu and a 140-year-old train schedule diagram.

• ### Get Public Transport Timetables

May 25, 2020

About two years ago, I shared an article about a project where I query and process results from the Google Transit API in a way that provides a simple overview for public transport connections between two places. Since I ended up using it rather frequently, I decided to turn it into a proper Python package, called gptt, available on GitHub and PyPI.

• ### A first endeavor into generative art

April 17, 2020

Last year we organized an internal conference at my workplace and I volunteered to put together a booklet with the abstracts of the presentations. I wanted to add photos of the authors, but I did not want them to look all the same.Actually, graphic design and layout editing was not new to me, I’ve always had a thing for this field. At some point during my bachelor’s in Economics I even considered moving abroad and studying it instead of finishing that degree. Instead of doing so, I just volunteered to design the faculty magazine. I came up with the idea to have the photos on top of two rectangles of the same size but of two different colors, a bit offset from the photo – every photo should be paired with differently offset rectangles to add some unique design. Of course, I did not want to do this by hand, but that’s what I know Python for.

• ### Introducing gpxslicer

January 28, 2020

I have recently released my first Python package, gpxslicer, a simple tool to cut GPX track logs into smaller segments. It is now available on GitHub and PyPI. The motivation behind creating it was simple: I wanted to automate tasks that I had done by hand too many times.

• ### Understanding Overpass, the API of OpenStreetMap

January 17, 2020

If you want to use spatial data from OpenStreetMap, OpenStreetMap is more than just a free map: it is also a free database of global geographical data. If you are not familiar with it, check out its Wiki to learn more. one way to get it is via Overpass, Read more about the Overpass API and its various endpoints here. a read-only API of the OpenStreetMap database. While the API is extremely flexible, its unique language, Overpass QL is not very intuitive. This article takes a very simple query and dissects it into its smallest pieces. This will help you understand (and write) such queries.

• ### Alphabetical sorting is hard

November 24, 2019

It really was a great idea. As usual, I took a problem that I randomly ran into and wanted to find a solution to. I was not sure if I could implement the solution, but I knew I could describe it. It happened when I was working on a project where I got some data about municipalities in Hungary. I thought it would be handy to sort them alphabetically so that the user of the final product can easily find the place they are interested in. However, due to the unusual letters in the Hungarian alphabet, such as ő or gy, collation is not trivial. But I knew I could find a way to solve this!

• ### The autumn of 1929 – the story of two hikes

October 29, 2019

I was going through the documents of my great-grandfather, Lajos Frenyó when I found a couple of folded papers in one of the notebooks. I had already known that he really liked hiking but I did not have any material proof of this hobby apart from the photo used as the cover image of this post. That is, up until that moment, because these papers contained a very detailed account documenting two trips in the Tatra mountains. This post contains these two reports with my comments.

• ### EXPECT A HAPPY HOBBY

December 2, 2018

Do you know what a COYOTE TOOTHACHE and a CHECKBOOK PHOTOCOPY have in common? If written in uppercase, all the letters of these expressions appear in the Cyrillic alphabet. That is, if we take a more relaxed definition of letters being the same shape: in many typefaces, K and К and Y and У do not look the same, just very similar. Although, to be precise, if somebody would try to read these using the Cyrillic alphabet, they would read “souote tootnase” and “sneckvook rnotosoru”, respectively.

I started thinking about this when I realized that I had never seen a Russian license plate with letters that do not also appear in the Latin alphabet. So I started to wonder about two things: is this observation true in general? If so, what words could we make up that would consist only of such letters?

• ### Nicely formatted transit schedules

August 18, 2018

I enjoy hiking, which most of the times involves using public transportation to get to the start of my hike and to get back home. Planning these trips used to be a major chore in Hungary before 2016, as there was no unified schedule database: one could only plan trips by train or bus, not together. During these times I came up with a timetable format in which I manually collected transit options using the bus and train planner websites as well as a map to came up with potential routes. These days transit information is available via the Google Directions API, so I decided to revisit this format and I developed a script that creates it automatically.

• ### Sunrise, sunset

March 8, 2018

I grew up in Budapest and moved to the Netherlands a few years ago. I could not ignore the fact that the Sun has very different patterns: it rises later and sets later here than in Budapest. However, this difference is not uniform: my feeling was that the sun rises much later and sets about the same time during the winter. I saw the inverse in the summer: Dutch summer evenings are much longer, but dawn does not lag behind that much. I wanted to verify this feeling in a scalable manner, so I created a website (code here) where you can pick two arbitrary locations on the globe and see a graph with their dawn/dusk times through the year.

• ### Where have the camels gone?

November 30, 2016

teveclub.hu used to be one of the most well-known websites among Hungarian teenagers. It is a Neopets clone where you can raise your own camel: feed it, and teach it various tricks day by day. I had the feeling that the site was slowly dying. I used data from archive.org to verify this hypothesis and I found that it was true: the total number of camels in the system has dropped from the ~320 thousand peak in 2006 to less than 26 thousand in 2018.

• ### Grab a drink while you wait for the bus

August 20, 2015

I always found it fascinating that there are several bus stops in Hungary which are called “{municipality name}, Cooperative Liquor Store” (szövetkezeti italbolt in Hungarian). It might get somewhat lost in translation that such a name very much reminds the reader of the socialist era it was given to the bus stop.

• ### Hungarian municiaplity name prefixes

August 6, 2015

Hungarian municipalities have unique names that consist of one (potentially compound) word. This was not the case until the end of the 19th century: multiple villages could have the same name, sometimes even in the same county. This caused trouble not only for the postal service but also related to taxation and conscription. Hence the standardization: every name must be unique; in case of a duplcate, the municipality names got a prefix based on their general location. I investigated these prefixes: their spatial distribution and the origin of those names.

• ### Bad idea of the day: toll on M0, the ring road around Budapest

December 11, 2014

An article published yesterday in Népszabadság reveals that the Hungarian budget for 2015 includes a proposal to introduce tolls on several motorway segments that are toll-free today. To me, this sounds like a bad idea.

• ### How far up does the tram go?

November 25, 2013

Historically, there were three relatively hilly tram lines in Budapest: 58, 59, and 61. Service on line 58 has been suspended since 1977. In this case, “suspension” includes the tracks having been removed and paved over. Based on this, I do not think service will restart anytime soon. But how far up do these actually go? And which one is the steepest?

• ### Revolutionary street names

March 15, 2013

Every Hungarian knows that almost every village in the country will have a street named after Lajos Kossuth, revolutionary and politician, and another named after Sándor Petőfi, an emblematic hero-poet – both of whom took part in the Hungarian Revolution of 1848. But where exactly are these streets?