When Geometry meets Geography
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Aznar, Ramiro
Geometry is clean, easy and polished. Geography is messy, dirty and unfitting. When we -geospatial developers and technicians- built applications to solve real life issues usually rely on the first. But eventually, we have to deal with the second. This talk is a very short sneak peak of a book I am writing to explain the most interesting cases I have experienced when working in the industry. Can a buffer tell me if I can take a walk to the nearest park? How a disputed territory such as Nagorno-Karabakh is displayed in a webmap? How geocoders understand the wide diversity of national postal systems? Geometry is clean, easy and polished. Geography is messy, dirty and unfitting. When we -geospatial developers and technicians- built applications to solve real life issues usually rely on the first. But eventually, we have to deal with the second. This talk is a very short sneak peak of a book I am writing to explain the most interesting cases I have experienced when working in the industry. Authors and Affiliations – Ramiro Aznar Geospatial Data Engineer at Planet Track – Transition to FOSS4G Topic – Data visualization: spatial analysis, manipulation and visualization Level – 1 - Principiants. No required specific knowledge is needed. Language of the Presentation – English
 Hello, everyone. Good morning, good afternoon. We are going to start with a new session in the very larger room. We have very, very interesting talks today. We are going to start with Ramiro Asnar. He's a geospatial data engineering at Planet. And he's going to talk about when geometry meets geography. Hello, Ramiro, welcome. Hello. Hello, everyone. Okay, I leave you to your talk. Okay, yeah. Thanks, Alba, for the presentation. Yeah, so, hello, Chabalada, how you are all having a really great conference. This is a talk that I have already given several times this year. And it's about a book that I'm currently writing. It tells the story of some of the geospatial applications that we are familiar with, GPS, geocoding, routing, web mapping, GIS, and the tech and limitation that are behind these technologies. It is half written, so there is a lot of research and writing to be made, even interviews as well. But before we start, let me switch to Spanish just for a second. Because I think that the things in the heart, I have to say them with your native language, I did not know Malena, only a few days in the Tanzania's Fosforgy, I thought I would see her again in person in Buenos Aires when this conference is celebrated. But well, I have very few memories of her and the same thing happens with many of the people who have left us there. And to not forget them, we must remember them. We must tell the stories we know of them, the people who met them. And well, that's how the memories will be fixed and our other people with whom we speak will extend Malena's life and the other people who have left us. Well, back to the talk. When geometry meets geography. So normally when we build, when we develop geospatial applications, our ideas, our code, our apps look like this, right? So geometry is clean, sharp, polished. But reality is more like this guy over here. Geography is messy, dirty and fitting. And yeah, in this book, I'm going to give some examples of this confluence, right? Of these meeting points. So the first chapter of this talk, not the first chapter of the book, is going to tell you, I'm going to tell you about the border. So during my time in Carto working in support, we usually got this type of image, right? So your map is wrong. So yeah, some of my viewers contacted us telling, telling support that Carto based maps were wrong. So the bond that is that they were referring to were located mainly in disputed territories such as Nagorno-Karabakh, Western Sahara, Kashmir. So Carto based maps were built as many, many others on top of OpenStreetMap. So we were using OpenStreetMap data. Well, there are some interesting tasks for to work with this idea. We didn't implement any of them. We were using kind of the default. And also these tasks were not being, as far as I know, that they are not like accepted by the whole community. Other based map providers use different approaches, different strategies. To be honest, I have no idea how Google does it behind the scenes, but you can see here an example that if you are in Morocco, you don't see the separation between the Western Sahara and Morocco. But if you are living in Morocco, then that's it. Like we'll be showing in your map. So it's shows you the layers based on your location. And some layers that are available in SRE servers and so on, they have also this, yeah, this symbology of the, you know, case four or solid four, depending on who is the viewer or where is the viewer. In Mapbox, there are only four specific options in the library plus the default. And that's, so they use like point of views, right? And this point of view can be the default or China, India, Japan and the US. And I will bet that Mapbox clients are based on these regions. And as you can see, it is kind of easy to implement, right? It's almost one line of code. And in this example, in this give, you can see like how the border is moving, depending on the Indian point of view or China's point of view. So this that looks like a game in our screens in our code in reality in the field looks like looks like this. So this is, I think this is a picture from the last conflict in Nagorno-Karabakh. So there are wars, migrations, isolations, there are people dying. So we should be aware of these lines and the geography that they represent. Okay, so the second chapter, it's roofing, right? And I will expect that many of you have done the typical workflow that is creating a buffer and then intersecting to get the points. And that's the typical error, let's say. And I have to confess that I have done it several times in my career. So let's take a look at another application. Imagine that you are an insurance company and you are covering the damage of an explosion. So your tool, the application that you run to figure out which clients are covered and which clients are not covered. The application uses a buffer, a one kilometer buffer from the explosion. And you got a complaint from a customer that is telling you that he is already within this one kilometer buffer, but the application is telling you otherwise. So who is telling the truth? So this idea came from a really nice talk from Sakavi, the CL. I really recommend taking a look. There is a link here in the presentation that will point you to the talk. So the idea is that many of the geospatial or all of geospatial applications build buffers simplifying the geometry. The issue is that a circle is an infinite number of points at the same distance of a center, right? And that cannot be modeled or visualized in a geospatial application. Of course, you can do this with things. For instance, using Pozzi IS, but if you want to visualize a circle, you need points to visualize the geometry. So that was the issue with this client, right? So because the application was simplifying the geometry, that point, that green dot in the left side of the left corner in the screen was left out. It was outside the borders of the circle. Another issue or another problem that we find when working with buffers is we have experienced this during the last lockdown. So I don't know if you remember, but many governments allow people to work a certain distance from their homes. In the case of Spain, it was up to one kilometer. So many applications such as this one that was made by the people from Geomatikos, it showed you the distance buffer from your place. But what happens when you have a barrier, right? Such as a river, a highway, and you know, the closer park from your place or the closer hospital or pharmacy is within the borders of this buffer. But in fact, if we use an isochrome, so instead of using just distance, there will be other places that are closer to your home, because in this particular case, you will need to cross the river. This is Valencia, and it's a longer work than the other places. So the third chapter is about one of my favorite topics that is geocoding. So this is the address of a hostel that I went like, I don't know, 10 years ago or so to Costa Rica. And for us, Europeans, it's kind of weird because we don't know if the hostel is in Avenue 6 or is it in Street 21 or Street 25. And what about the second line? This is the La Iglesia Sagrada Operazón 100 metros norte, 50 oeste. So it's telling us like a relative position. So it's from one chart, 100 meters north, 50 meters west. So for us, it's kind of a strange. So if we look at the map, this is the Street 25, this is the Street 26. This is Avenue 6. So it's kind of framing us where the hostel is. And also this is the chart that we were, that the second line was saying. So it tells us that we need to go 100 meters and then 50 meters in north and west. So probably this is the place that we are looking for. And in fact, it is. But it has to show you that the way that the post that goes work is different from one place to another. And yeah, so I used the example of Costa Rica, but of course the Japanese way of structuring street addresses is quite different. So it's using blocks instead of street names and what is striking and it's kind of surprising to people who don't live in Japan or in Tokyo is that the numbers of the blocks are being set up based on the age of construction. So you really need someone local to the community or a special application to move around a Japanese city. So these are just two examples to show you the complexity of other postal codes in the world. But even our own ones, we assume too many things. And this is a link that shows you kind of a list of things that we think it's real in when we write, let's say more occidental or more European or US centric kind of postal codes. And there are many, many, many, many issues concerning these assumptions. Yeah. So next time that you type something in a text box that it's going to hit your code in API, think about these things because it's kind of amazing how they are able to translate these expectations. They know where our home is, right, where we work as well. So it's something that is really, really interesting and I love doing the research that I've been doing in the book. Yeah, so the final chapter, it's kind of a bonus. Yeah, I would like to end this talk giving you some ideas to think about afterwards. So there is a lot of debate about how social media, like YouTube recommends new content to users, but I haven't seen any similar approach in your space application. Maybe I'm wrong and I'm missing something, right? So I can imagine something like the Explorer of Planet, one of the apps that my company is currently developing, that you are exploring a part of the world and you get like an image. So the application can recommend you, okay, if you have seen this hardware city that is in the north of Spain, maybe you are interested in another Spanish hardware city or another north European city or another city that is really close that it has also a hardware. You know, so this is just an idea. And lastly, I have been playing with OpenAI GPT-3 model, so you can ask them many, many, many things and it's kind of amazing how the conversation or how the response develops. And you can ask the model to, you can ask the model some geospatial questions and it's quite funny. But what is so surprising is that most of the time it's accurate. And you are, if you ask about the distance between cities or how many cities are within the range of, you know, one kilometer from a specific place, because it has a connection with Wikipedia, I guess. I mean, it has been trained with all these URLs, all this data that is internet. Wikipedia should be there as well, I guess. That's really cool. So yeah, it would be great if we can have something like more specific for geospatial. Yeah, that's something that it would be great to see. Okay, so yeah, that's it. Yeah, many thanks. Yeah, if you have any questions, yeah, let me know. Thank you, Ramiro. That was a very, very nice presentation. I really liked it. All the concepts that you presented, sometimes we forget about them, so they are very important, especially not forgetting that we are mapping territories that are inhabited by people and societies that influence them and we had to take them into account. So I think that was a great presentation. There were some comments in the chat for you. A lot of people is relating to these problems about different addresses, different codes, postal codes. So I think a lot of people was also interesting in all of these concepts. Please post your questions in the question pool or comments. Here a lot of people is saying thanks, great reminder of key concepts and also wishing you luck with the research and the drafting. So very nice comments in the venue list for you. Okay, while I wait for more questions. No, for now, I will give the link to in the, I will post the link of the templates so you can all have them. If you wish, I will, if you want, I will invite you to give this talk in the university I teach because I think students will love it. So we can keep in touch because I really like it. So congratulations for that. Okay, I don't see. Okay, I have a question here. When do you expect your book to release? Yeah, hopefully, probably the end of next year. Because as I said, it's half written. So, and it's been one year since I started reading the issues that I'm not, I have to work as well. So yeah, it's too much. But I, yeah, I've been having a great time and so maybe I will spend like one month, I don't know, one month, one week of my vacation just focusing on that and maybe I can speed up. But yeah, I will say it like next year, probably the last quarter of this year of 2022. Okay, we are looking forward for that. So there are some other questions. Have you found any reports of issues caused by changing in DATOMS over time, locations moving? No, to be honest, I have kind of skipped the projection issue because it's like a, yeah, it's a big Pandora box and there are people who are more knowledge about projections and photography. But yeah, I'm going to make a notation because that's a good idea. Okay, great. Are you going to make any maps for your book that you are excited about? That's a really good question. Yeah, because it's kind of a moreative, creative kind of book because I also tell the story of how these technologies have been built over the years. Yeah, there will be maps but easy ones, more schematics than, yeah. Okay. Well, someone is asking about boundaries in Mauritius domain. So in the sea, but he missed the, he or she missed the first part of the presentation. So I posted the link of the slides already. But if you want to post also your contact details, I can share in the venue list, your email. Yeah, regarding the boundaries, the sea boundaries, no, I haven't because the chapter about the territories, the disputed territories is not still written. But that's something that I will need to investigate as well because it's, especially now with the Brexit and so on. It's interesting. Okay, great. If there isn't any more questions, I think I, yep, I tell them all. You can also then go to the venue list to see all the comments. There are very interesting comments in the chat and some feedback. So it was very nice. Okay, thank you very much, Ramiro. We can say goodbye. Yeah, let's keep in touch. Yeah, yes, I will write to you.
 Hello, everyone.  Good morning, good afternoon.  We are going to start with a new session in the very larger room.  We have very, very interesting talks today.  We are going to start with Ramiro Asnar.  He's a geospatial data engineering at Planet.  And he's going to talk about when geometry meets geography.  Hello, Ramiro, welcome.  Hello.  Hello, everyone.  Okay, I leave you to your talk.  Okay, yeah.  Thanks, Alba, for the presentation.  Yeah, so, hello, Chabalada, how you are all having a really great conference.  This is a talk that I have already given several times this year.  And it's about a book that I'm currently writing.  It tells the story of some of the geospatial applications that we are familiar with, GPS,  geocoding, routing, web mapping, GIS, and the tech and limitation that are behind these  technologies.  It is half written, so there is a lot of research and writing to be made, even interviews as  well.  But before we start, let me switch to Spanish just for a second.  Because I think that the things in the heart, I have to say them with your native language,  I did not know Malena, only a few days in the Tanzania's Fosforgy, I thought I would  see her again in person in Buenos Aires when this conference is celebrated.  But well, I have very few memories of her and the same thing happens with many of the people  who have left us there.  And to not forget them, we must remember them.  We must tell the stories we know of them, the people who met them.  And well, that's how the memories will be fixed and our other people with whom we speak  will extend Malena's life and the other people who have left us.  Well, back to the talk.  When geometry meets geography.  So normally when we build, when we develop geospatial applications, our ideas, our code,  our apps look like this, right?  So geometry is clean, sharp, polished.  But reality is more like this guy over here.  Geography is messy, dirty and fitting.  And yeah, in this book, I'm going to give some examples of this confluence, right?  Of these meeting points.  So the first chapter of this talk, not the first chapter of the book, is going to tell you,  I'm going to tell you about the border.  So during my time in Carto working in support, we usually got this type of image, right?  So your map is wrong.  So yeah, some of my viewers contacted us telling, telling support that Carto based maps were wrong.  So the bond that is that they were referring to were located mainly in disputed territories such as Nagorno-Karabakh,  Western Sahara, Kashmir.  So Carto based maps were built as many, many others on top of OpenStreetMap.  So we were using OpenStreetMap data.  Well, there are some interesting tasks for to work with this idea.  We didn't implement any of them. We were using kind of the default.  And also these tasks were not being, as far as I know, that they are not like accepted by the whole community.  Other based map providers use different approaches, different strategies.  To be honest, I have no idea how Google does it behind the scenes, but you can see here an example that if you are in Morocco,  you don't see the separation between the Western Sahara and Morocco.  But if you are living in Morocco, then that's it.  Like we'll be showing in your map.  So it's shows you the layers based on your location.  And some layers that are available in SRE servers and so on, they have also this,  yeah, this symbology of the, you know, case four or solid four, depending on who is the viewer or where is the viewer.  In Mapbox, there are only four specific options in the library plus the default.  And that's, so they use like point of views, right?  And this point of view can be the default or China, India, Japan and the US.  And I will bet that Mapbox clients are based on these regions.  And as you can see, it is kind of easy to implement, right?  It's almost one line of code.  And in this example, in this give, you can see like how the border is moving, depending on the Indian point of view or China's point of view.  So this that looks like a game in our screens in our code in reality in the field looks like looks like this.  So this is, I think this is a picture from the last conflict in Nagorno-Karabakh.  So there are wars, migrations, isolations, there are people dying.  So we should be aware of these lines and the geography that they represent.  Okay, so the second chapter, it's roofing, right?  And I will expect that many of you have done the typical workflow that is creating a buffer and then intersecting to get the points.  And that's the typical error, let's say.  And I have to confess that I have done it several times in my career.  So let's take a look at another application.  Imagine that you are an insurance company and you are covering the damage of an explosion.  So your tool, the application that you run to figure out which clients are covered and which clients are not covered.  The application uses a buffer, a one kilometer buffer from the explosion.  And you got a complaint from a customer that is telling you that he is already within this one kilometer buffer, but the application is telling you otherwise.  So who is telling the truth?  So this idea came from a really nice talk from Sakavi, the CL.  I really recommend taking a look.  There is a link here in the presentation that will point you to the talk.  So the idea is that many of the geospatial or all of geospatial applications build buffers simplifying the geometry.  The issue is that a circle is an infinite number of points at the same distance of a center, right?  And that cannot be modeled or visualized in a geospatial application.  Of course, you can do this with things.  For instance, using Pozzi IS, but if you want to visualize a circle, you need points to visualize the geometry.  So that was the issue with this client, right?  So because the application was simplifying the geometry, that point, that green dot in the left side of the left corner in the screen was left out.  It was outside the borders of the circle.  Another issue or another problem that we find when working with buffers is we have experienced this during the last lockdown.  So I don't know if you remember, but many governments allow people to work a certain distance from their homes.  In the case of Spain, it was up to one kilometer.  So many applications such as this one that was made by the people from Geomatikos,  it showed you the distance buffer from your place.  But what happens when you have a barrier, right?  Such as a river, a highway, and you know, the closer park from your place or the closer hospital or pharmacy is within the borders of this buffer.  But in fact, if we use an isochrome, so instead of using just distance, there will be other places that are closer to your home,  because in this particular case, you will need to cross the river.  This is Valencia, and it's a longer work than the other places.  So the third chapter is about one of my favorite topics that is geocoding.  So this is the address of a hostel that I went like, I don't know, 10 years ago or so to Costa Rica.  And for us, Europeans, it's kind of weird because we don't know if the hostel is in Avenue 6 or is it in Street 21 or Street 25.  And what about the second line?  This is the La Iglesia Sagrada Operazón 100 metros norte, 50 oeste.  So it's telling us like a relative position.  So it's from one chart, 100 meters north, 50 meters west.  So for us, it's kind of a strange.  So if we look at the map, this is the Street 25, this is the Street 26.  This is Avenue 6.  So it's kind of framing us where the hostel is.  And also this is the chart that we were, that the second line was saying.  So it tells us that we need to go 100 meters and then 50 meters in north and west.  So probably this is the place that we are looking for.  And in fact, it is.  But it has to show you that the way that the post that goes work is different from one place to another.  And yeah, so I used the example of Costa Rica, but of course the Japanese way of structuring street addresses is quite different.  So it's using blocks instead of street names and what is striking and it's kind of surprising to people who don't live in Japan or in Tokyo is that the numbers of the blocks are being set up based on the age of construction.  So you really need someone local to the community or a special application to move around a Japanese city.  So these are just two examples to show you the complexity of other postal codes in the world.  But even our own ones, we assume too many things.  And this is a link that shows you kind of a list of things that we think it's real in when we write, let's say more occidental or more European or US centric kind of postal codes.  And there are many, many, many, many issues concerning these assumptions.  Yeah. So next time that you type something in a text box that it's going to hit your code in API, think about these things because it's kind of amazing how they are able to translate these expectations.  They know where our home is, right, where we work as well. So it's something that is really, really interesting and I love doing the research that I've been doing in the book.  Yeah, so the final chapter, it's kind of a bonus. Yeah, I would like to end this talk giving you some ideas to think about afterwards.  So there is a lot of debate about how social media, like YouTube recommends new content to users, but I haven't seen any similar approach in your space application.  Maybe I'm wrong and I'm missing something, right?  So I can imagine something like the Explorer of Planet, one of the apps that my company is currently developing, that you are exploring a part of the world and you get like an image.  So the application can recommend you, okay, if you have seen this hardware city that is in the north of Spain, maybe you are interested in another Spanish hardware city or another north European city or another city that is really close that it has also a hardware.  You know, so this is just an idea.  And lastly, I have been playing with OpenAI GPT-3 model, so you can ask them many, many, many things and it's kind of amazing how the conversation or how the response develops.  And you can ask the model to, you can ask the model some geospatial questions and it's quite funny.  But what is so surprising is that most of the time it's accurate.  And you are, if you ask about the distance between cities or how many cities are within the range of, you know, one kilometer from a specific place, because it has a connection with Wikipedia, I guess.  I mean, it has been trained with all these URLs, all this data that is internet.  Wikipedia should be there as well, I guess.  That's really cool. So yeah, it would be great if we can have something like more specific for geospatial.  Yeah, that's something that it would be great to see.  Okay, so yeah, that's it.  Yeah, many thanks.  Yeah, if you have any questions, yeah, let me know.  Thank you, Ramiro. That was a very, very nice presentation. I really liked it.  All the concepts that you presented, sometimes we forget about them, so they are very important, especially not forgetting that we are mapping territories that are inhabited by people and societies that influence them and we had to take them into account.  So I think that was a great presentation. There were some comments in the chat for you.  A lot of people is relating to these problems about different addresses, different codes, postal codes.  So I think a lot of people was also interesting in all of these concepts.  Please post your questions in the question pool or comments.  Here a lot of people is saying thanks, great reminder of key concepts and also wishing you luck with the research and the drafting.  So very nice comments in the venue list for you.  Okay, while I wait for more questions.  No, for now, I will give the link to in the, I will post the link of the templates so you can all have them.  If you wish, I will, if you want, I will invite you to give this talk in the university I teach because I think students will love it.  So we can keep in touch because I really like it. So congratulations for that.  Okay, I don't see. Okay, I have a question here. When do you expect your book to release?  Yeah, hopefully, probably the end of next year.  Because as I said, it's half written.  So, and it's been one year since I started reading the issues that I'm not, I have to work as well. So yeah, it's too much.  But I, yeah, I've been having a great time and so maybe I will spend like one month, I don't know, one month, one week of my vacation just focusing on that and maybe I can speed up.  But yeah, I will say it like next year, probably the last quarter of this year of 2022.  Okay, we are looking forward for that. So there are some other questions. Have you found any reports of issues caused by changing in DATOMS over time, locations moving?  No, to be honest, I have kind of skipped the projection issue because it's like a, yeah, it's a big Pandora box and there are people who are more knowledge about projections and photography.  But yeah, I'm going to make a notation because that's a good idea.  Okay, great. Are you going to make any maps for your book that you are excited about?  That's a really good question. Yeah, because it's kind of a moreative, creative kind of book because I also tell the story of how these technologies have been built over the years.  Yeah, there will be maps but easy ones, more schematics than, yeah.  Okay. Well, someone is asking about boundaries in Mauritius domain.  So in the sea, but he missed the, he or she missed the first part of the presentation. So I posted the link of the slides already.  But if you want to post also your contact details, I can share in the venue list, your email.  Yeah, regarding the boundaries, the sea boundaries, no, I haven't because the chapter about the territories, the disputed territories is not still written.  But that's something that I will need to investigate as well because it's, especially now with the Brexit and so on.  It's interesting.  Okay, great. If there isn't any more questions, I think I, yep, I tell them all.  You can also then go to the venue list to see all the comments. There are very interesting comments in the chat and some feedback.  So it was very nice. Okay, thank you very much, Ramiro.  We can say goodbye.  Yeah, let's keep in touch. Yeah, yes, I will write to you.
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