Tagged: maribor

Slovenian business activity by city as animated heatmaps

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A few months ago, while researching business times of various categories of establishments in Slovenia,  I thought it would be nice to somehow visualize a map with a graphical representation of density of open establishments. I decided on heatmap style, although I later discover that my chosen implementation had some drawbacks.

Getting the data

Data with business hours of commercial establishments is traditionally not open for many reasons, two of them being that (1) this information can be commercially exploited, and (2) the opening hours can be subject to frequent changes, which can tax the database owner with considerable effort should the database stay current and reliable.

First I toyed with the idea of crawling entire  directory of odpiralnicasi.com, then I actually thought about making a version for London, Amsterdam or San Francisco with Yelp data, for which I would have to crawl an entire Yelp city directory, a task I’m not sure it would succeed. Yelp would probably block my IP before I could harvest a significant portion of what interested me.

So I decided I would use the Najdi.si maps business directory. Disclosure: I work there, so I have access to the database with various business data, which is being kept current.

For every company, I took out only the name, geo coordinates, business hours and business category, then I constructed the animated maps. Before I delve into that, a short video of economic activity in Slovenia in course of a typical Monday.

Economic activity in Slovenia from Marko O’Hara on Vimeo.

The animated chart you see on the bottom shows the number of active establishments in various economic categories, such as Restaurants and catering, Industry, Shopping, etc. The full list is:

  • blue: Computers and IT,
  • red: Restaurants and catering,
  • green: Home and garden,
  • yellow: Beauty and health,
  • pink: General business,
  • orange: Free time,
  • violet: Industry,
  • magenta: Culture and schooling

Rendering the maps and constructing the visualization

Rendering one frame in one city at a specific time is just a matter of setting appropriate latitude, longitude and zoom level on the map, selecting the desired time and plotting on the map all establishments  that are open at that time. I used Processing to do that, and for the heat map part I used this excellent example by Philipp Seifried. As a finishing touch, I made maps to switch between day and night styles at appropriate times.

To do entire video, I had to write a parallel rendering queue lest the rendering of a single video took an eternity – Eclipse project available by email request.

To complicate things a bit I decided to include up to four different places on the same map, so the viewer could compare opening hours in Ljubljana in different economic categories, or see how different cities woke up and went to sleep at different times.

A typical frame looks like this:

Video frame / comparison of business activity in Nova Gorica, Koper, Celje and Novo Mesto at noon
Video frame / comparison of business activity in Nova Gorica, Koper, Celje and Novo Mesto at noon

Here’s an example for different economic activities in Ljubljana:

Economic activity in Ljubljana – four categories from Marko O’Hara on Vimeo.

  • top left: General business
  • top right: Restaurants and catering
  • bottom left: Industry,
  • bottom right:Beauty and health

Here’s a comparison between Ljubljana and the city of Maribor:

opentimes ljmb.mp4 from Marko O’Hara on Vimeo.

  • left: Ljubljana
  • right: Maribor

And here a comparison of business activity in Nova Gorica, Koper, Celje and Novo Mesto:

opentimes kpnmceng.mp4 from Marko O’Hara on Vimeo.


  • top left: Nova Gorica
  • top right: Koper
  • bottom left: Novo Mesto,
  • bottom right:Celje



I mostly did this to be able to visually compare levels of business activity in Ljubljana. First of all, the heatmap technique I employed here turned out to be somewhat unreliable for video purposes, because it colors the dots relative to the highest concentration. But concentration and absolute numbers of active businesses change from frame to frame, so it seems that at night there’s more activity that during the day.

Even so it’s still clear that restaurants, bars and clubs are still pretty much open when other activity starts to die down.

This is Ljubljana at noon, again:

  • top left: General business
  • top right: Restaurants and catering
  • bottom left: Industry,
  • bottom right:Beauty and health

The big spot in the northeast is the mall region, where untold number of business operate in ten or more big malls. Business concentration there dwarfs everything else in the city, except maybe in industrial category.

lj at 11 h

Below is Ljubljana at eight o’clock in the evening. Pretty much everything has closed down except for eating and drinking, and maybe the cinema theater in the mall.


Below: Ljubljana at ten o’clock in the evening. Some businesses don’t close down at all. I double checked the primary data source and it’s true. There are cleaning services that stay open during the night, etc.


I’m relatively satisfied with results except for the heatmap issue. I may correct that if I get the data for a bigger city.

Slovenian real estate prices mapped

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There has recently been a flurry of activity by self-made mappers on the net that major media have noticed. It seems that proliferation of tools such as the excellent TileMill does help to make custom maps a relatively painless, yet still laborious process.

In my experience, a major hurdle in this process is getting good data. Governments and corporations around the globe have made acquiring the goods easier, but the quality frequently leaves one wanting. More about this particular dataset later.

This map is my attempt to visualize real estate prices in Slovenia. Buildings are colored according to the most expensive unit they contain, except in some cases where data is bad. More below.

See the map!

A map of real estate prices in Slovenia.

A map of real estate prices in Slovenia.

About the dataset

This dataset is provided by GURS, a government institution. I used it before, to make the map of structure ages in Ljubljana. It comes in a variety of formats, such as SHP (geometry) and text (building properties) files, which were clearly dumped from database tables.

It has some severe problems. For example, some bigger and more expensive buildings contain many units, but these units all hold the same value regardless of their useful area. To make matters more complicated, other multiunit buildings don’t hold the same value for the units they contain. They are, in other words, evidenced correctly. Then, there are building compounds, like the nuclear power plant in Krško, in which every building clearly holds the exorbitant value of entire compound. Some other buildings have price value as zero, and so on.

All of this doesn’t even start to address the quality of valuation the government inspectors performed. In the opinion of many property owners, the values are too low. There’s a new round of valuation coming, in which the values are reportedly bound to drop by further five to twenty percent, if I remember correctly. It will be interesting to make another map with the valuation differences some day.

Massaging the data

This means that the above map is my interpretation of the dataset beyond the visualization itself. In calculating values for visualization, there were several decisions I made:

  • For multiunit buildings, I calculated the cost of square meter for every unit, then colored the building with color value of the most expensive unit. This was necessary, because some buildings contain many communal areas, garages and parking lots, which are all independently valued. I first tried with a simple average value, but the apartment buildings with many parking boxes and garages were then valued deceivingly low. I tried to make the map more apartment-oriented, so this was a necessary decision to make it more accurately reflect the market.
  • For incorrectly evidenced buildings with same value (high) unit value, I took the price of one unit, divided by sum of unit areas. I could do this on one unit only, but which one? There’s no easy answer. The average seemed the way to go.

I also made a list of the most expensive buildings by their total Euro value. Individual unit values were summed, except in cases described in the second bullet point above. there I simply took the price of one unit. It’s accessible as a separate vector layer under “Most expensive buildings” menu item.


Turns out the most expensive buildings are mostly power plants, which is not surprising. In Ljubljana, two of the most expensive buildings were completed recently. Well, the Stožice stadium was not really completed. I don’t know whether it was paid for or not – this is a discourse best suited for political tabloids. See the gallery:

It’s also hardly surprising that the capital and the coast are areas with the most expensive real estate available. The state of city of Maribor is sad to see, though, at least in comparison to Ljubljana.

I suggest taking the tour in the map itself, where I go into a little more depth for some towns and cities. Also, be sure to click the “Most expensive buildings”, then hovering the mouse pointer over highlighted buildings to get an idea of their total cost and price per square meter, which in many cases diverges dramatically.

Here are two charts showing price/m2 distribution at different intervals in time.
This one is an all-time chart. Most buildings are valued low, since all ages were taken into account.

This one shows the period between year 2008 and now, in other words, since the crisis struck. Nevertheless, more expensive buildings seem to prevail. No wonder, since they are new. But that probably also means that there’s more apartment building construction relative to countryside development. I’m not really a real estate expert, so if anyone has a suggestion, comment away.



Inspiration for the tour was this excellent visualization by the Pulitzer center.

I also have to thank the kind people at GURS for providing me with data. They know it’s flawed somewhat, but all in all it’s not so bad.


As I’ve noted before, this map is a result of my interpretation of government data. I’m in no way I responsible for any misunderstandings arising from this map. If you want to see the actual valuation of your building or building unit, please consult GURS or use their web application to find out.

See also

Structure ages map in Ljubljana.

Dance away on Eternal Dancefloors (interactive art project with Kinect)

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Do you like to dance? I do. So, one morning in Berlin, after a long partying night, I was going back home with a friend, and a morbid theme came up: why do we have to be buried or cremated after death, and not taxidermied, implanted with an robotic skeleton, animated with your own previously movements, and let to dance the eternity away?

Turns out there are some good and some strange reasons why the state won’t let you get taxidermied, even if you specifically requested it. Vsauce has a very good video about it on Youtube. Plus the idea of someone remodelled into a robotic puppet and then sold, resold, stored in an attic by embarrassed grandchildren, or even uploaded with a new animation, can soon get uncomfortable.

Nevertheless, we set out to create a foundation to do just that, if only to exist as an art project. The first phase is a system to capture motion of a visitor with a computer, store it in an accessible format, an visualize the whole thing as a big dancefloor, where the subject can dance with recordings of previous visitors. We’ll decide on following phases as we go, maybe Google will release a low-cost robotic skeleton someday. We can use it to convert ourselves and launch into space to dance eternally on Noordung‘s space station.

Some screen footage (sorry for low resolution, shot with a phone):

It’s essentially a motion-capture program that visualizes dancers’ motion on a virtual dancefloor and stores 3D-data for later use. For motion capture we used one Kinect, for 3D animation  Processing, and for rendering the excellent OpenGL library GLGraphics. Captured data is stored in a SOLR index to be searchable by dancer’s name.

The whole procedure goes like this: the visitor comes into Kinect’s field of view and is instantly recognized without need to strike any pose. Countdown to recording starts, and after ten seconds a ten-second clip of visitor’s movement is recorded, while the visitor can watch his movements on screen and synchronize movements with previously recorded dancers. It’s more fun to dance in company after all. Here’s the whole “workflow” in video. It’s choppy, but it’ll do.

The installation was premiered on Maribor Electronica Days in Maribor, Slovenia, on February 15th, 2013, sponsored by Kibla. Shown through house videographer’s lenses it looked like that:

video: Matej Kristovič, shown at: Festival MED in Maribor organized by ACE KIBLA.

The project in original form was shortlisted for Robots and Avatars  last year, but we unfortunately didn’t win. The name was a little bit more convoluted, I think Eternal Danceflooors is better than 1st Stage Preparations for a Taxidermic Afterlife Party, as it was then titled.

There was a lot of big talk in project documentation. Read this if you can:

‘1st Stage Preparations for a Taxidermic Afterlife Party’ is a part of a planned wider ‘Taxidermic Afterlife Party’ project, which is firstly addressing the problem of the disappearing intergenerational solidarity through the creation of taxidermic dancing afterlife avatars.

As a conceptual starting-point we take the present situation, where society’s mechanisms are less and less able to provide for it’s older – i.e., “non-functional” – members. As a response to this phenomenon we strive to establish an absurd dystopian vision of a situation that has gone out of hands, where we have got real physical avatars with no reasonable purpose, but they do not want to go away (are present after individual’s life) and on top of this also need to be up kept (because we deal with real prepared human bodies – containing a dance mechanism – that need to go dancing / clubbing, as they function on the basis of the Tamagotchi principle).

The artists themselves are of course submitting their bodies to this artistic project as an act of social comment.

Because of the fact that in our society you have got only three options of what can be done with your body (burial, cremation or liquefaction), one of the aims of this 1st stage is the assertion of the right to get prepared after death. Individuals that are taking part in this project are also signers of this claim (although you can take part and not sign the claim and vice versa). This whole vision might be dystopian in its core, but there is also something romantic in dancing just a little bit longer …

In the history of human kind, dance is one of the oldest forms of expression, social interaction and establishment of collective identity; it was a part of first rituals, also meant to change each individual neural activity in order to reach this state of collective identity. Vanishing of this phenomenon or its limitation to club environment in today’s society on one hand, and flourishing use of social networks on the other, makes it interesting to put this ”primitive praxis” (dance) in the context of new technologies (virtual environment).

Stages of the whole lifelong and afterlife project:
– 1st: establishment of the dance moves database with visualization and interaction platform and functionality for asserting the right to get prepared after life via a petition
– 2nd: getting in touch with competent and/or suitable institutions (e. g., cyborg foundations) resulting in actual preparation
– 3rd: taxidermic afterlife party: embodiment of recorded database by actualization in a robotic platform
– 4th (“sad-but-true” future vision): you / your avatar will probably get sold on eBay, stored in some dusty garage, your dance moves are going to be hacked to sadly entertain the owner’s drunken friends … But no one is saying that the first exemplar is not going to end up in Guggenheim.

We have a process here where the dancing human body is substituted by a digital representation (caught with motion capture) and later on the digital representation gets substituted again by the real body (prepared body with an implanted robotic mechanism). The whole project is resulting then in reversing the process where we establish an avatar through the omission of the real body and make our own personality avatar’s content – now this at one point “abandoned” dimension (i.e., the real body) becomes the avatar …

The 1st stage of the project includes an interactive installation, where individuals record their dance moves through the usage of motion capture, and the development of an online virtual environment. This interauthorship (individuals contributing to the database of dance moves) can be seen as an investment into individual’s future presence and also as a contribution to the future presence of others, as the project is based on the creative commons principle. The database can be understood as a prospect for your own and others’ afterlife presence, but also as a part of the responsive environment, in which individuals enroll and take an active part in it in this lifetime. People would be called to get their digital dancing avatars through announcements / appeals in mass media.

The 1st stage can be interpreted as a project in itself with following outputs:
– (world’s largest) database of freestyle party dance moves, including moves by professional dancers and supporters of the project
– online virtual environment, i.e., visualization and interaction platform for recorded dance moves
– a base of exclusive music sets contributed by well-known artists
– a formal claim for a right to get prepared after death.

I hope you enjoyed the videos.

There is another one, shot in development phase:

Project authors:

Pina Gabrijan (concept and organization)

Marko Plahuta (concept, programming and art)