An open geographic data format based off of JavaScript Object Notation

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4
votes
2answers
381 views

How to merge TopoJSON features?

I currently have a coordinate based map of the US and it's states for topojson (https://github.com/mbostock/topojson). The coordinates are a JSON array (as topojson works), data looks like this: ...
4
votes
2answers
367 views

Where can I find GeoJSON resources files?

I'm looking for demographic information and various things, and most of the time data are available as CSV (my application use geoJSON format). Shall I encode the CSV to geoJSON or is there a ...
4
votes
2answers
1k views

Beginner needs suggestions on map clicks and geojson

I'm a beginner with programming, and javascript. I went to the FOSS4G-NA conference and was very inspired to learn more. I'm trying to learn PostGIS, and have come across a very useful tutorial for ...
4
votes
1answer
915 views

What's up with the GeoJSON spec and CRS as a IRM?

I'm writing a web API to our GIS data, currently revamping our geocoding service. I'm creating the option for folks to specify the output type as GeoJSON so I'm trying to follow the spec. Our data is ...
4
votes
2answers
974 views

GeoJSON/GeoCouch questions from a newb [duplicate]

I am new to JSON and GeoJSON and would like to start to use this but I am a little confused about some things. Perhaps you can help me out: 1) Is there a GeoJSON validator out there? 2) Is the text ...
4
votes
2answers
247 views

How to remove redundant points

We basically have points table including vehicle routes.In huge traffic conditions,devices collecting data on route may output redundant points where at any coordinate same points may repeat.We can ...
4
votes
2answers
1k views

Using QGIS, how can I add a bounding box attribute?

I have a shapefile where I am exporting the features to GeoJSON objects with ogr2ogr based on a simple where clause. One thing that I would like to be included in the GeoJSON object is the 'bbox' ...
4
votes
1answer
212 views

Geotools: Efficiently writing a GeoJSON stream into a Shapefile

I've been trying a few solutions to efficiently convert GeoJSON into a shapefile without having to store all features in memory. I'm using GeoTools 9.2. The problem is not so much in how to stream ...
4
votes
2answers
398 views

binding nested arrays as geojson popups in leaflet

I am struggling with geojson popups in leaflet.js I have nested arrays as properties for my features - an example would be counts of fish caught at a location (not my actual project data!) ...
4
votes
1answer
2k views

Auto zoom on multipolygon with leaflet

I have a geojson with a multipolygon and I want to fit this multipolygon to the map. The map center only on one polygon not on the multipolygon. Here is my script var map = L.map('map',{ ...
4
votes
1answer
638 views

Why are GeoJSON coordinates different exported from QGIS vs. ogr2ogr?

I have a shapefile with a Google Mercator projection (900913) that I need converted to GeoJSON. I need to do this on a regular basis amongst other things so I wrote a shell script to do it using ...
4
votes
1answer
95 views

How to generate image tiles from custom geo data for use with Leaflet

Migrating a webapp from Google Maps API V3 to OSM + Leaflet, which displays custom data that consists of lots of lines and points, on a background map. When this custom data is drawn by Leaflet on ...
4
votes
1answer
386 views

Generate tiles for google maps overlays

I am trying to show some information on Google Maps which would be in the form of translucent circle overlays. The problem is that some circles overlap, which results in increased opacity and blending ...
3
votes
2answers
1k views

Convert GML to GeoJSON

I have downloaded a GML file from Statistics Canada and would like to convert it into GeoJSON to use parts of it in a D3 visualization on the web. However, I did not find a converter that would do ...
3
votes
2answers
125 views

Problem with loading GeoJSON file in OpenLayers generated by PHP

I'm trying to read some geo-data from PostGIS database using PHP, creating a GeoJSON file and showing it on a base map using OpenLayers. The PHP code works just fine. The generated data in GeoJSON ...
3
votes
2answers
1k views

Is there any efficient way to convert Geojson to WKT?

I want to use ST_GeomFromText() to load vector data to PostGIS. However, I don't know how to convert from Geojson type to WKT. N.B. I know I can use OGR2OGR to upload the geojson directly, but I just ...
3
votes
2answers
188 views

Is it possible to check incoming GeoJSON to see if any of the features are identical to existing ones before adding to map?

I am working on a Rails/PostGIS app and doing a typical ajax call to retrieve GeoJSON within the map viewport bounds. Whenever the map is shifted or zoomed all of the markers are removed and then ...
3
votes
2answers
210 views

GeoJSON formatting for Leaflet

I am using http://GeoJSON.io as the source for my data, which is then to be displayed via Leaflet.js. I found that leaflet neads the file to include "var name = {" but GeoJSON.io doesn't like it, ...
3
votes
3answers
907 views

Definitions and limitations of MapInfo TAB file objects

I am working on a MapInfo plugin to convert MapInfo files to GeoJSON files. I am having trouble matching up the object types of the two formats. Each GeoJSON object type is described in the ...
3
votes
1answer
79 views

Serialize python list containing geometry

In simple case if list doesn't contains geometry all works fine: result = [dict(f.fields, id=f.id, label=f.label) for f in features] json.dumps(result) But if result list contains geometry ...
3
votes
2answers
170 views

How to generate one geojson file from several rows in Postgres/PostGIS?

I have a table with geospatial objects, in particular, polygons. I know that I can generate from one row a geoJSON string using ST_AsGeoJSON(http://www.postgis.org/docs/ST_AsGeoJSON.html). But I would ...
3
votes
1answer
404 views

My GeoJson will not display on a Vector Layer in Openlayers

I have geoJson from the the USGS that I am downloading to my server. It validates just fine with geojsonlint. When I past the JSON into this Openlayers example it says it is bad input json. My Code ...
3
votes
3answers
440 views

How to properly convert landmass NaturalEarth data into GeoJSON?

100% Newbie. I've been following Mike's d3 Map Tutorial and I've come up against a challenge. I guess my question essentially boils down to: how does one generate the proper GeoJSON/TopoJSON files ...
3
votes
1answer
645 views

How to avoid corrupt geometries when translating between TopoJSON and GeoJSON?

I'm trying to display some geojson vector features on a leaflet map. The size of my GeoJSON is too big (25.4mb of data, 8.47mb gzipped), so I'm trying to use a TopoJSON format to reduce the size ...
3
votes
1answer
355 views

What is generally faster in OpenLayers: WMS or GeoJSON?

I work both with WMS (connection with postgres) and GeoJSON in OpenLayers. I have the impression that a WMS is faster when more feature need to be loaded. And I have the impression that GeoJSON is ...
3
votes
2answers
1k views

Getting json feature id on OpenLayers

I'm projecting some features using json format on OpenLayers. I need to get the id from the feature (not the OpenLayers' id but the one in the json file). The file looks something like this. ...
3
votes
1answer
2k views

Parsing a GeoJSON file with jQuery

I'm trying to iterate through a GeoJSON file (below) and eventually populate an array with a few attributes within "properties". I keep coming up short working through various examples I can find. Do ...
3
votes
1answer
856 views

OpenLayers GeoJSON Data Store

Background: I have a single geoJSON data object that backs multiple Vector Layers of its features. I do this because the feature data has many attributes and can be presented in many different ways, ...
3
votes
2answers
114 views

Performance loss for OpenLayers EPSG transformation? Storing GeoJSON coordinates in lat/lon or in native map projection?

For a project the map projection is EPSG:32468 (tiles). On top of the map, two or three GeoJSON LineStrings should be displayed using OpenLayers. Each LineString has about 1500 coordinates. ...
3
votes
1answer
2k views

How do you put GeoJSON attribute information in a popup with OpenLayers

I am having some trouble putting GeoJSON attribute information in a pop-up. The selection control is working, and I create an alert (for testing) and this is working. But I can't figure out how you ...
3
votes
1answer
384 views

Change Layer name when converting from GeoJSON

I am converting GeoJSON files to other formats (including KML) using ogr2ogr. As you may know, there is no field in a GeoJSON file to specify the name of the layer, causing every conversion to have ...
3
votes
1answer
2k views

OpenLayers & GeoJSON files

After some hunting, it seems that if I have an a geojson file, I NEED the data and map to be on a server in order to view this in OpenLayers because of the protocol class. I saw an example where I can ...
3
votes
1answer
30 views

Convert Sql Server Spatial data to GeoJSON & plot on map

I have a sql server table with Geo spatial data. An example of row would be (with Column names): type: streetline code: 231001 geog: 0xE6100000011 ........ Centroid 0xE61000000C....... geom: ...
3
votes
1answer
1k views

problem adding pop-up to GeoJSON layer in Leaflet

I'm new to working with the Leaflet API and am running into trouble with creating popups for a GeoJSON layer. I've looked at the following post as a reference and am still having difficulty: binding ...
3
votes
3answers
159 views

Extracting Earthquake Depth from the USGS GeoJson Earthquake Feed for use with Openlayers

I have some GeoJson from the USGS as follows: {"type":"Feature","properties":{"mag":4.3,"place":"30km ESE of Jarm, ...
3
votes
5answers
350 views

How can I count overlapping polygons, resulting in a new set of polygons?

I have 100 polygons in a GeoJSON file that partially overlap each other. I would like to produce 100 new polygons as follows: The area covered by any of the original 100. This is their union. The ...
3
votes
1answer
352 views

ogr2ogr from Postgres to GeoJSON missing crs key

I'm using ogr2ogr to convert some OSM data for Greenland (not really important for the question), from a PostGIS database to a file containing GeoJSON. The problem is that the GeoJSON gets written ...
3
votes
1answer
2k views

How to add a geoJSON layer to leaflet map?

i am newbie in leaflet & its geojson features... I am trying to test leaflet's functionalities. In fact i have built a map and its layer: var map = new L.map('map', {scrollWheelZoom:true, ...
3
votes
1answer
94 views

Why is the exterior shell of this GeoJSON invalid?

I got some data from Zillow's neighborhood database as shapefiles and converted them to GeoJSON. However, some of the objects appear to be malformed when inserting them into MongoDb. Is there ...
3
votes
1answer
253 views

Offline Phonegap/Openlayers App

I have a mobile app that uses Phonegap with OpenLayers and Geoserver. Now, I need to make the app available completely offline. The amount of data points can get very large depending on what client is ...
3
votes
2answers
391 views

Display GeoJSON layer on top a SVG image instead of a map.

I'm very new to GIS, so hope this is the correct place to ask. Not sure if this will even be possible. This is what I want to achieve: In short, I want to display a set of polygons, lines etc. in a ...
3
votes
0answers
230 views

What are the default units of elevation/altitude/z in GeoJSON?

The GeoJSON spec says "The default CRS is a geographic coordinate reference system, using the WGS84 datum, and with longitude and latitude units of decimal degrees". It doesn't say seem to specify ...
3
votes
0answers
113 views

How do I clip Geojson FeatureCollection with another Geojson polygon

I have a GeoJSON file that contains one FeatureCollection with a bunch of features that are polygons. I also have the boundary of the continental USA in another GeoJSON file. I'd like to clip the ...
3
votes
0answers
69 views

Can QGIS give GeoJSON layers a meaningful default name?

When I add a GeoJSON layer to my QGIS project, it always gets the name OGRGeoJSON. This is in contrast with shapefile layers, which seem to be named after the file name by default. Is there a way to ...
3
votes
0answers
119 views

GeoJSON support in ArcObjects 10 .NET

i am currently trying to build a geoprocessing application using OpenLayers and ArcObjects, I have some features that user draws on openlayers and i need to send these features to arcobjects for ...
2
votes
4answers
3k views

How to convert SHP into GPX or JSON?

I would like to convert the tree inventory shape files of London (Canada) into a GPX file and if possible into a JSON file. You can download the archive from their Open Data website. It contains the ...
2
votes
2answers
3k views

How to load external geojson file into leaflet map

I would like to load a geoJSON (polygon) file into my leaflet map. I have seen examples where geoJSON is embedded into the javascript code but I can't find any examples showing how it is done with an ...
2
votes
3answers
461 views

Can ArcPy's AsShape be used with GeoJSON FeatureCollection of Polygons with Labels?

The AsShape documentation provides examples that work very well. However, I have been given what I believe to be valid GeoJSON that is a FeatureCollection of two polygons each with a Label. It ...
2
votes
1answer
304 views

ogr2ogr specify lat/long order on conversion to GeoJSON

When using ogr2ogr to convert a polyon from a .shp file to GeoJSON, I noticed that it writes the coordinates in order lat, long. I noticed this because whenever I tried to view the GeoJSON on a map, ...
2
votes
2answers
143 views

animate polygons in series of kml/geojson/shp

I have a series of KML files (though they could easily be converted to geoJSON, SHP, or anything else that ogr2ogr can handle), each file containing a set of polygons that correspond to the alpha ...