An open geographic data format based off of JavaScript Object Notation

learn more… | top users | synonyms

6
votes
1answer
235 views

How do I represent the whole Earth as a Polygon?

This is related to determining the interior of a Polygon. My difficulty is that if I specify a Polygon covering the Earth going from East to West, it will still have a boundary along the ...
5
votes
3answers
2k views

How to convert geoJSON to python objects?

New to the site, and to geoJSON, and to python. My goal is to read in a file with geoJSON data, and use it to generate shapes to be used in an application that is using python scripting. Python has ...
5
votes
3answers
789 views

Can we merge shapefiles with different geometries (point and polygon) to get a single layer which shows both geometries?

I want to merge two shape files in which one is of point geometry type and other is polygon type in order to get a single layer containing both points and polygon in a single map.
5
votes
3answers
645 views

Is there a API which return the geojson data for a countries borders?

Is there a simple free REST API where I can send the name or code of a country and get in return geojson data which highlights it's borders ? I'm writing an application where I will have a changing ...
5
votes
1answer
178 views

Is there a free dataset of historical geocoordinates of ancient cities and places?

Is there a freely available dataset (csv, geojson, topojson, etc.) with geocoordinates of ancient cities, for example of the Roman Empire? Ideally with additional information like population size? ...
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 ...
5
votes
1answer
250 views

Conventions for returning GeoJSON via an API

I have a queryable API that returns one or more GeoJSON FeatureCollections. Currently the response looks something like this: { "success": { "data": { "layer1": {"type": ...
5
votes
2answers
875 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 ...
5
votes
2answers
97 views

Access geojson from github in leaflet

I am new to json, github, and leaflet. But I am trying to create a simple application which will render my points which are in geojson up on github. From everything I have read this should work. ...
5
votes
1answer
3k 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 ...
5
votes
1answer
1k views

Real time positioning of vector features using database

I am a newbie in GIS and want to implement something like a vehicle tracker wherein I will get a series of coordinates in a database. I have no idea how to go about it, I mean what should my process ...
5
votes
2answers
356 views

How can I setup a simple web mapping system?

I'm new to mapping and GIS and I'd like to setup a mapping system to display informations on a map, I think the following could work but I'm not sure how good it is.. 1- I store my data (lat, lng ...
5
votes
2answers
284 views

Leaflet: How to enable pan & zoom while GeoJSON still rendering?

I've overlaid a huge GeoJSON geometry on top of my Leaflet map, covering about 20 countries' borderlines (about 1,5 million vertices) using "L.geoJson". Each time I zoom in/out, the computer has to ...
5
votes
2answers
977 views

OGR merge shapefiles of different geom type into a single GeoJSON feature collection

I'd like to merge shapefiles of different geometry types into a single geojson feature collection, but OGR says it doesn't support update of GeoJSON files: $ ogr2ogr -f GeoJSON -t_srs crs:84 -lco ...
5
votes
2answers
2k views

Create multiple vector layers by reading a GeoJSON file once in OpenLayers

I am a begginner to OpenLayers, and my question is about making things more efficient. My work is about displaying time-dependent weather elements on several point locations on the map. All these ...
5
votes
1answer
482 views

Leaflet - Change style on click

I am beginer with Leaflet library and I am facing an issue with a geojson. I have an extern geojson file (points) and I would like to display a circle for each point coordinates and get a bigger ...
5
votes
2answers
837 views

Large loads geojson from mysql to leaflet?

I have a mysql database with +25K rows including geometry and other attributes. Using a mysql2geojson php script I then added it to a leaflet map. It is super slow now, what can I do to boost the ...
5
votes
1answer
792 views

Exporting Arcgis Online content as georss or geojson? [duplicate]

There are number of sites talking about how to add a georss feed to an ArcGIS Online map (see silverlight and flex examples from esri_webapi), but I haven't located anything about exporting a georss ...
5
votes
1answer
942 views

Working examples of Leaflet/Polymaps with GeoJSON tiles generated from Tilestache using Shapefiles?

I'm looking to create choropleths using GeoJSON tiles generated from ESRI Shapefiles by TileStache(or similar), in either Leaflet or Polymaps. So far reading and drawing GeoJSON from both Leaflet and ...
5
votes
1answer
964 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
2answers
2k 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 ...
4
votes
2answers
1k 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
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 ...
4
votes
1answer
529 views

Is there an XML equivalent to GeoJSON?

In my web application, I am retrieving geospatial data from a server backend (Java) to the browser frontend (JavaScript). I am considering two options of how to serialize the data in this ...
4
votes
3answers
3k views

MySQL to GeoJSON - Formatting Issue

I'm trying to make a select on a mysql table and then write it out to a geojson file. I'm getting close but there are a few issues. Here's what I have so far: <?php require("dbinfo.php"); // ...
4
votes
2answers
1k views

Online WKT and GeoJSON viewer

I once found a great but simple webpage that has a drop down with several text-based GIS formats such as GeoJSON and WKT, and a text box to copy/paste your data. The feature is then drawn on a world ...
4
votes
4answers
2k 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 ...
4
votes
2answers
480 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
2answers
1k views

Reproject GeoJSON in OpenLayers 3

I'm basically trying (and failing) to replicate this in OpenLayers 3. I've set up a fiddle here: http://jsfiddle.net/vu8ecy8v/5/ I'm under the impression that OpenLayers will reproject a GeoJSON ...
4
votes
2answers
1k 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
3answers
293 views

Adding Properties to GeoJSON File

I have a GeoJSON file of the country of Haiti with the administrative boundaries for communes (i.e. counties). Here is the file: ...
4
votes
1answer
175 views

Day and night zone layer for Leaflet

I'm working with Leaflet and I'd like to show the day and night zones adding a dynamic layer to my map. I was thinking to add a static layer with some transparency and make it move every x minutes but ...
4
votes
2answers
533 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
2answers
874 views

Is it valid to have a properties element in an geoJSON featureCollection?

Is it valid to have a properties element with a featureCollection-element as parent? This is, according to geojson.org valid: { "type": "FeatureCollection", "features": [ { "type": ...
4
votes
1answer
70 views

Dump a GeoJSON FeatureCollection from Spatialite query with Python

Given a Spatialite database, holding a table with a geometry column and some other attribute columns. I want to query that table in a Python script and get a GeoJSON FeatureCollection string in return ...
4
votes
1answer
1k views

SQL query to have a complete geojson feature from PostGIS

I would like to get a geojson feature with properties from PostGIS. I have found an example to have a feature collection but I can't make it works for just a feature. so far I tryed to modify the ...
4
votes
1answer
248 views

Leaflet: how to change default style on a point GeoJSON Layer?

I need to change style on a point GeoJSON layer in a Leaflet map. I'm using the following code: function onEachFeature(feature, layer) { if (feature.properties && ...
4
votes
2answers
694 views

get map tiles for a polygon

Based on this tutorial, I can easily find out a tile for a point. But is there an algorithm to find all tiles that are covered by a rectangle or lineString or by any other feature? I would greatly ...
4
votes
3answers
1k 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: ...
4
votes
1answer
760 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
1answer
562 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 ...
4
votes
2answers
867 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

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, ...
4
votes
2answers
813 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
4answers
712 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 ...
3
votes
2answers
174 views

How to determine number of features in GeoJSON file using Python or JavaScript?

Is there a best way to determine the number of features in a GeoJSON file? Ideally using Python or JavaScript.
3
votes
2answers
754 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
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); } ...