An open geographic data format based off of JavaScript Object Notation

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3
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3answers
383 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
769 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
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 ...
3
votes
2answers
446 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 ...
3
votes
1answer
598 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
4k 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
2answers
413 views

How can we generate GeoJSON from SQL data with latlong

Is there any way we can create GeoJSON from SQL server table with Latitude & Longitude Data?
3
votes
0answers
1k views

How can a leaflet SVG overlay be placed outside of the leaflet-overlay-pane?

I have SVG on top of GeoJSON in my map. How can a leaflet SVG overlay be placed outside of the leaflet-overlay-pane while keeping GeoJSON in place in the leaflet-overlay-pane? (For example, how could ...
3
votes
1answer
541 views

How to get data from TileMill tileLayer properties in Mapbox for click/hover

I've successfully used Leaflet to load a geoJSON polygon-shapefile with data, and added click and hover interactivity to the layer. For a large dataset, I switched to mapbox.js 1.6.1, used TileMill to ...
3
votes
0answers
56 views

simple raster format to use in Web applications?

I'm building a Web application in which users create and edit very coarse raster data. They're assigning values to cells in a georeferenced grid. Right now I'm storing the values in a multidimensional ...
3
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0answers
147 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
2answers
446 views

How to export thousands of features from PostGIS to a single GeoJSON file?

I know how to export one feature from a PostGIS database using ogr2ogr: $ogr2ogr -f GeoJSON out.json "PG:host=localhost dbname=xxx user=xxx password=xxx" -sql 'select id, county, wkb_geometry from ...
2
votes
4answers
5k 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

Add GeoJSON layer to OpenLayers 3

I have a GeoJSON file called mygeojson.json and I want to add it as a layer in OpenLayers 3 on top of an openstreetmap layer. So far I could display the openstreetmap world including zoom etc. but for ...
2
votes
3answers
235 views

FME and elasticsearch

We are developing a system to disseminate information about roadkills. The source data comes from three different databases. We have set up a FME project which pulls geojson from the source databases, ...
2
votes
5answers
286 views

What are some ways to convert a csv file to geojson while preserving data types?

Assuming said csv file is properly structured with Latitude and Longitude. I'm having problems find converters that won't mess up the data types (putting string around integers).
2
votes
3answers
2k views

Convert Shapefiles to GeoJSON?

I'm trying to convert Shapefiles from the State of Texas Senate Districts website into a GeoJSON file for use with Google Maps API. I'm using QGIS to facilitate but I can't get the ...
2
votes
2answers
967 views

How to project a geoJSON file in OpenLayers?

I have a json file well formed. I want to read a json file as a base layer from OpenLayers. <script type="text/javascript"> var styles = new OpenLayers.StyleMap({ ...
2
votes
2answers
78 views

Coordinate Not Match - Convert Shapefile to Geojson

I'm a newbie at GIS programming and I have a problem with file conversion. I've tried to convert shp file to geojson, and the coordinates do not match. But when I try to convert it to kml, it goes ...
2
votes
2answers
396 views

What's the best way to determine if a point is within a certain distance of a GEOJSON polygon?

What's the best way to determine if a point is within a certain distance of a GEOJSON polygon? Should one use TurfJS buffer method (https://github.com/Turfjs/turf-buffer#turf-buffer)? Can one perform ...
2
votes
3answers
4k views

How to change Leaflet marker color on mouseover?

I'm having a hard time figuring out why the Leaflet method setstyle will change the color of a polygon but not the color of my markers. Polygon works fine: But the markers won't change colors: ...
2
votes
2answers
331 views

Remove unneeded columns from geographic data file?

I have some GML data that has some unneeded columns in it. I'd like to remove these columns in order to reduce the file size. (To clarify: I mean that the file has many points in it, and each of these ...
2
votes
1answer
133 views

When do GeoJSON feature collections need feature ids?

I've seen feature collections with feature ids for each feature. I've seen others with no featureid. When do you need it?
2
votes
2answers
1k views

Leaflet.geojson webpage performance out of hand, how to convert to .png?

I exported some countries as a single .geojson file. The file includes every country's vertices and coordinates, as that's what a .geojson is ─ a vector file. Thing is, there are about 20 countries ...
2
votes
3answers
848 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
2answers
2k views

leaflet and geojson tiles

New to mapping. Trying to create a heat map with data that updates every hour for US Counties with leaflet.js similar to http://leaflet.cloudmade.com/examples/choropleth-example.html. But, adding ...
2
votes
1answer
1k views

Openlayers dynamic filtering/styling of geojson layer

I'm working with Openlayers and overlaying a geojson file representing species type over OSM. I have an HTML form that allows users to select a species type and I then need to filter the geojson layer ...
2
votes
3answers
685 views

How to create a efficent linestring out of geography points using postgis

I'm trying to create a linestring out of geography points. At the moment I'm doing it like this: select ST_GeographyFromText(ST_Makeline(a.record_point)) from ( select (record_point::geometry) from ...
2
votes
1answer
200 views

Accessing geojson properties using OpenLayers3

Is it possible to access geojson properties using the OpenLayers library? I tried to search for it but couldn't find any proper answer. According to my research, the library converts each geojson ...
2
votes
1answer
548 views

shapefile for mumbai area or section wise

I am working on a project in which i need to plot data on Mumbai city map section wise or area wise but i am not able to get Shapefile for the same. Can anyone please provide me the link where i can ...
2
votes
1answer
279 views

OpenLayers and GeoJSON

Recently I started learning Openlayers 2x and I've been struggling for a while now with a GeoJSON and it's projections. So, here is the deal; I successfully added wms layers from ( ...
2
votes
1answer
222 views

My woes rendering shape files on web-based mapping application

First, I'd like to let it be known that this is my first journey into developing mapping applications with such a large set of data. So, I am in way locked into the techniques or technologies listed ...
2
votes
1answer
107 views

Access to custom GeoJSON members in OpenLayers 2

I need to read a layer-wide attribute, from a GeoJSON file, set by a custom member to the object: {"type": "FeatureCollection", "features": [...], "search_polygon": "POLYGON (...)"} Since it seems ...
2
votes
2answers
612 views

How do I convert open street map export to geojson?

I am trying to render this output from open street map into geojson to add into a map. I only need to export the data one time. How do I do that? OSM lists it as a use case. I see a js library to do ...
2
votes
2answers
367 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 ...
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
2answers
1k 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?
2
votes
3answers
602 views

GeoJSON generator with OpenLayers support

Is there a service that allows me to draw on an OpenLayers map, and see the resulting GeoJSON?
2
votes
1answer
1k views

Polymaps Project + Geojson + D3

How are you doing ? I am Mehul Nahar working on a project which is similar to http://www.tableausoftware.com/learning/examples/gpa-analysis. I have used Polymaps platform, where I have used cloudmade ...
2
votes
1answer
505 views

Store a GeoJSON FeatureCollection to postgres with postgis

I am new to GeoJSON. I have a GeoJSON features collection as shown and would like to store it in postgres table (testtable). My postgres table has a serial id and geometry column. { "type": ...
2
votes
4answers
274 views

How can I publish a Google Sheet to the web as a GeoJSON file?

I am trying to create a map in Mapbox to be embedded on a website and have the embedded map automatically update every time the source data is updated. I have my source data in a Google sheet and have ...
2
votes
2answers
92 views

How to encode a point geometry in Geojson?

I have point geometry in posgresql which I query as follows: select ST_AsText(geom) as pointgeom from pointable. I'm using python as server side script. I want to pass the result as Geojson response ...
2
votes
1answer
295 views

How to get a table from a leaflet map?

I have a map Here based on leaflet JS and the layers are geojson. I would like to get a table at on another div when I click on each layers. How would I be able to do that? Thanks
2
votes
2answers
211 views

PHP examples to replicate FeatureServer capabilities

I used FeatureServer before and I liked it. The only thing I didn't like, though, is that it needs some other dependencies to work. That's why I want to try PHP instead. I know that there are already ...
2
votes
1answer
212 views

Unicode Decode Error for shapefile in Python

I have Python script for converting shapefiles to Geojson. My code works well if I use some usa data, but when I want to use some other encoding, it gives me this error: Traceback (most recent ...
2
votes
1answer
78 views

GeoJSON and HTML/JavaScript vs Shapefile and Silverlight

I'm developing a map application (Several shapefiles with OpenstreetMap or BingMap on background and some dynamically generated features on the map). I'vs created some part of it with Telerik RadMap ...
2
votes
2answers
122 views

Row-crop field boundaries

I'm on the hunt for field boundary coordinates in the US in the form of GeoJSON, a Shapefile or any structured format that I can use to overlay on a map. I've tried looking at the US Department of ...
2
votes
1answer
374 views

Merge multiple linestring features into a single multilinestring

Using QGis or ogr2ogr how do I convert a vector file containing multiple linestrings features into a single multilinestring feature? At the moment I've been doing this manually by converting the data ...
2
votes
1answer
490 views

Converting JSON/GeoJSON files to Shapefiles

I have a quick question please about converting JSON/GeoJSON files. I'm trying to convert some JSON files into something I know how to work with (shapefile, R objects or PostGIS). I'm afraid I have ...
2
votes
2answers
322 views

Sending map extent in (geo)JSON

I have a leaflet map that I need to fitBound on a given rectangle. The coordinate for the fit bound will be transfered in JSON via a REST call on a server. We are using GEOJson to encode our geometry ...