7 items tagged “geospatial”
2022
lon lat lon lat lon. Tom MacWright’s definitive guide to the (latitude, longitude) v.s. (longitude, latitude) debate. The answer is frustrating: both orders are used by significant software, so there’s no single answer that will satisfy everyone. I’ve recently been mostly convinced over to the longitude, latitude side mainly because that’s a better fit for the non-geospatial x, y pattern. # 10th February 2022, 4:32 pm
2019
kepler.gl. Uber built this open source geospatial analysis tool for large-scale data sets, and they offer it as a free hosted online tool—just click Get Started on the site. I uploaded two CSV files with 30,000+ latitude/longitude points in them just now and used Kepler to render them as images. # 25th October 2019, 4:16 am
2017
Building a location to time zone API with SpatiaLite, OpenStreetMap and Datasette
Given a latitude and longitude, how can we tell what time zone that point lies within? Here’s how I built a simple JSON API to answer that question, using a combination of data from OpenStreetMap, the SpatiaLite extension for SQLite and my Datasette API tool.
[... 2185 words]2010
Geospatial Indexing in MongoDB (via) New in version 1.3.3. Handles “order by distance from” queries using a geohash approach under the hood, automatically searching nearby grid squares until the correct number of results have been gathered. Bounding box search is planned for a future release. # 2nd March 2010, 8:12 pm
2009
JS-Placemaker—geolocate texts in JavaScript. Chris Heilmann exposed Placemaker to JavaScript (JSONP) using a YQL execute table. Try his examples—I’m impressed that “My name is Jack London, I live in Ontario” returns just Ontario, demonstrating that Placemaker’s NLP is pretty well tuned. # 23rd May 2009, 12:36 am
Flickr Shapefiles Public Dataset 1.0. Another awesome Geo dataset from the Yahoo! stable—this time it’s Flickr releasing shapefiles (geometrical shapes) for hundreds of thousands of places around the world, under the CC0 license which makes them essentially public domain. The shapes themselves have been crowdsourced from geocoded photos uploaded to Flickr, where users can “correct” the textual location assigned to each photo. Combine this with the GeoPlanet WOE data and you get a huge, free dataset describing the human geography of the world. # 22nd May 2009, 6:12 pm
Yahoo! Geo: Announcing GeoPlanet Data. The Yahoo! WhereOnEarth geographic data set is fantastic, but I’ve always felt slightly uncomfortable about building applications against it in case the API went away. That’s not an issue any more—the entire dataset is now available to download and use under a Creative Commons Attribution license. It’s not entirely clear what the attribution requirements are—do you have to put “data from GeoPlanet” on every page or can you get away with just tucking the attribution away in an “about this site” page? UPDATE: The data doesn’t include latitude/longitude or bounding boxes, which severely reduces its utility. # 20th May 2009, 9:12 pm