An open geographic data format based off of JavaScript Object Notation

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3
votes
1answer
1k views

display a choropleth map using D3 and Leaftlet

I am trying to get a leaflet map to display a choropleth map using d3. I have written this code using samples I have found however the map just displays as the black fill, not the color classes I ...
0
votes
0answers
161 views

Openlayer seems slow when zooming / panning on vector (geometry line) from geojson. Why?

I have a layer with 7 lines . when I zoom on some of the lines , the maps seems to be very slow. I thought it might be because I bring a lot of points to the client (that represents the line) aa ...
0
votes
1answer
87 views

VSI File API support in ogr2ogr

It seems that support for streaming input is wishy-washy in ogr2ogr. For example, why can I do this: curl "http://data.usgin.org/arizona/wfs?service=WFS&version=1.1.0& ...
2
votes
1answer
118 views

Which fields are standardized to describe a ShapeFiles feature?

I would like to store data into a database which is available here either as JSON or as ShapeFiles. The JSON looks something like this: { "type": "FeatureCollection", "features": [ { ...
2
votes
1answer
407 views

Programmatic conversion between GML and GeoJSON

I am modifying a .Net (C#, MSSQL) system to add some geography that I'd like to display on a leaflet map. I had originally expected to save GeoJSON directly into text strings in the DB, but after ...
1
vote
1answer
6k views

How can I change the style of marker in leaflet (from GeoJSON)?

I'm serving GeoJSON to leaflet and by default it get a blue icon marker. I'm trying to change the style so I'll be able to use the feature properties as part of the style , but no matter what I do , ...
1
vote
1answer
535 views

GeoJSON is valid according to JSONLint but jquery gives error

I have the following GeoJSON (from webservice) { "Features": [ { "Id": "1", "Geometry": { "Coordinates": [ { "Latitude": 31.2812, ...
2
votes
0answers
182 views

Show geoJSON properties in jQuery Mobile Panel

First off I'm a novice at JS so please bear with me if this is a simple task to complete. I'm currently using the stock LeafletJS popup bubble to display the properties from my geoJSON. However, I ...
0
votes
1answer
1k views

Building SQL statement in javascript and casting variables as strings

I'm working with Postgres 8.3/PostGIS which is storing some polygons. I'm writing a javascript function which will take in a parameter of a watershed id from another function. The javascript will ...
1
vote
1answer
826 views

GeoJSON in Leaflet

I'm just starting to work with leaflet and have a basic question about showing a geoJSON file. First, I found this excellent article with example code: http://bl.ocks.org/lxbarth/4019660 However I ...
2
votes
3answers
477 views

Is GeoServer getting coordinate output in GeoJSON WFS wrong?

When I do a WFS request to GeoServer and specify the SRS like this: http://myserver.com/geoserver/wfs? service=wfs& version=2.0.0& request=GetFeature& ...
2
votes
0answers
264 views

R, GeoJSON and Leaflet

I recently learned about leafletjs.com from an R-Bloggers.com post. One such tutorial that I would like to achieve is to create interactive choropleth maps with leaflet. I have been using the rjson ...
3
votes
3answers
426 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 ...
0
votes
2answers
969 views

How to create multiple polylines using an external geoJSON file using Leaflet?

I'm starting with Leaflet and I'm using some georeferenced information collected from twitter. I already manage to load an external geoJSON with some points. But now I wan't to draw some connections ...
2
votes
2answers
906 views

How to determine intersection between geojson feature and given coordinates?

I'm overlaying a leaflet map with features of geojson, fetched with d3 and added as SVG elements to the DOM. My geojson contains too many features to render at once, so my goal is to add to the map ...
0
votes
0answers
92 views

Is there a big (if any) performance difference between Geoserver SQL Layer and OpenLayers geojson Layer?

I have a table with multiline geography items in SQL Server 2008 (Routes). I want to show them on OL Google Map but I'm having trouble creating SQL Data source in geoserver (something related to ...
1
vote
1answer
115 views

Can a GeoJSON GeometryCollection contain another Collection?

From a reading of the spec it seems that a GeometryCollection is a Geometry and can contain geometry objects? But I want to be sure that this is really allowed before I file a bug report.
3
votes
4answers
1k 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
378 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 ...
0
votes
2answers
352 views

PHP PostGIS to geoJSON missing required parametar error

I'm using this PHP PostGIS to geoJSON script: https://gist.github.com/bmcbride/1913855 But I keep getting this error: 'missing required parameter: geotable' This is my code: # Retrive URL ...
1
vote
2answers
329 views

Can't read returned geojson

I've got a function that takes an Openlayers mouse click and puts the click location into a SQL statement which then gets passed to a JSP script which runs the SQL statement on the PostGIS database ...
1
vote
1answer
213 views

How do you make a function for changing projection with proj4js in Openlayers?

I have included Proj4js in OpenLayers. I would like to create a function (so I can use a make a button). To change the projection of my map. I have included in javascript Proj4js.defs["EPSG:54008"] ...
0
votes
2answers
124 views

How do you get all info from GeoJSON layer in Openlayers?

In OpenLayers I have added a GeoJSON layer (of the world) and created a simple infotool. The GeoJSON layer contains multiple features for some countries. If I click on a country I only get one ...
1
vote
1answer
227 views

OpenLayer and not well formed Json

I am learning to use GeoExt and OpenLayers, and I want to reproduce one of the examples given at the geoExt website. The script call a GeoJSON containg the position of Alp summits. I downloaded it via ...
0
votes
1answer
1k views

Loop over features of a GeoJSON object from CartoDB

I have just little knowledge about HTML and JavaScript. Nevertheless I was playing, copying and pasting around with Leaflet and CartoDB. I want to display the features GeoJson in a table. This is ...
1
vote
2answers
379 views

Looking for a GeoJSON describing the french departments

Is there any place where I could find a GeoJson describing the borders of the french departments, or do I have to convert a .shp file?
1
vote
1answer
527 views

Attribute editing in QGIS on geoJson file

We have vector files in the format of geoJson files. We need to keep it in geoJson format as it is picked up by mobile devices via Restful services. The problem is we want to change the attributes of ...
0
votes
1answer
271 views

geojson -> topojson : no output

Trying to convert my geoJSON file into topoJSON so I downloaded topojson from npm and followed the instructions on gis.stackexchange Convert GeoJSON to TopoJSON basically the same as the topoJSON ...
-2
votes
1answer
67 views

Render specific vector data from database with openlayer

I want to render some data on a map. They are stored as points in my database (postGiS), each one is associated with a name. I want to render points with the same place name in the same color. ...
3
votes
2answers
2k 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 ...
1
vote
1answer
1k views

How to get correct format of coordinates for export to geojson from QGIS?

I've created a custom map in QGIS with a few shapefiles. I'm using leaflet.js to render the map and the shapefile points and everything lines up correctly. The CRS is set to 4326. When I export the ...
0
votes
0answers
609 views

How do I add elevation data to a GeoJSON line from a GPX file?

I understand that elevation can be added as an optional third value in Coordinates (lat, long, elev) in a geojson file, but I can't find a way to actually do that from a gpx file. I've used ogr2ogr to ...
0
votes
1answer
644 views

PostGIS error reads “Geometry has Z dimension but column does not” [duplicate]

I try to store a polygon in GeoJSON format into my PostGIS table. Both are using the CRS EPSG:3857. This is how the polygon is defined. Note that I put in some whitespace to make it more readable. { ...
8
votes
3answers
4k views

How to insert a GeoJSON polygon into a PostGIS table?

I need to insert a polygon from GeoJSON to my PostGIS table. This is how the SQL query looks like. INSERT INTO tablename (name, polygon) VALUES ( 'Name', ST_GeomFromGeoJSON ( { ...
3
votes
3answers
1k views

How to add a polygon from PostGIS ST_AsGeoJSON into Leaflet?

I try to use the following function to add polygons to my Leaflet map. function polygon(geojson) { alert(geojson); // alert for testing layer = L.geoJson(geojson); layer.addTo(map); } ...
2
votes
1answer
2k views

Conversion from Shapefile to TopoJSON format results in incorrect map when rendered using d3js

I am trying to build a map of Canada showing FSA boundaries using d3js. I got shape data from Statistics Canada ...
2
votes
1answer
283 views

Kartograph Open Street Maps

Firstly, congratulations to Gregor Aisch for creating such a wonderful library, thank you! I am having a little trouble rendering an svg from some osm data. I downloaded the Sweden transportation ...
3
votes
2answers
142 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. ...
1
vote
4answers
321 views

Does shapefile or MapInfo TAB have advantage as source format for OGR conversion to GeoJSON?

I'm relatively new to OGR and GIS in general. Most of the sources I look at give a choice of ESRI shapefile and MapInfo formats. I'm using ogr2ogr to convert these to GeoJSON for import into ...
5
votes
3answers
1k views

Interacting between Openlayers and Python

I have a openlayers website like this one that gives the user the ability to draw polygons and then creates a GeoJSON file. I want to process this GeoJSON with a python script. The python script ...
2
votes
1answer
213 views

SQL Command to convert pgRouting result to GeoJSON

My goal is to produce a Web UI for pgRouting using this tutorial. I have already imported my data from an OSM pBF to PostGIS using osm2po. Using the pgRoutingLayer plugin for QGIS, I was able to ...
0
votes
1answer
166 views

Saving part of OSM shapefile in QGIS as GeoJSON strips 'name' field to 25 characters long [duplicate]

I want to copy part of OSM data in ESRI Shapefile (downloaded from http://download.geofabrik.de/europe/ukraine.html ) and save in in GeoJSON to style later in Tilemill. After saving, I see that ...
1
vote
1answer
83 views

BBox missing when converting TIGER to GeoJSON

I can't get the bounding boxes of polygons if TIGER/Line shape files when converting them to GeoJSON using FWTools. The other default information is present and there is no difference between the ...
2
votes
2answers
780 views

GeoJSON to Shape file conversion with geotools

Can someone please provide me an example of how to convert GeoJSON to Shape file using geotools?
1
vote
1answer
710 views

What is the best way to use Leaflet and Geoserver to highligh a feature after a WMS request?

I have a web map, and I'm hoping to make it interactive. The layer I have is reasonably large, at 15 mb in GeoJSON format 4 mb compressed, so I don't want to load the whole layer as one file. But, I ...
1
vote
1answer
472 views

Reprojecting coordinates and geoJSON in leaflet

I have a Leaflet map in default projection and a wms layer also in default (web mercator) projection. I would like to add polylines and a geoJSON layer to my map, but the coordinates are in EPSG4326. ...
2
votes
1answer
148 views

Natural Earth: How to get the position of all provinces that belong to a state

This question is about Natural earth 1:10 states and provinces.shp file. I'm using ogr2ogr and want to know the name of the id i need to pass . In purpose of pulling out the right states regions. ...
2
votes
1answer
275 views

leaflet geojson contextmenu

I want to add a context menu on right click for various elements on my geojson layer (I'm doing a road map so on a right click on the road at any part I want to show the context menu). I've managed ...
0
votes
1answer
939 views

GeoJSON Get Request MVC 4

I'm having trouble creating an OpenLayers Vector layer with GeoJSON data in an MVC 4 application. The GET request for my json file always comes back with a 404.3 error - page cannot be served ...
4
votes
1answer
2k views

leaflet geojson coordinate problem

I just started to play with leflet/geojson a little. But my coordinates are not rendered properly and I have no clue what is going on. My coordinates are: 52.23943, 4.97599. They work correct with ...