An open geographic data format based off of JavaScript Object Notation

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2
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2answers
54 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
225 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
2answers
987 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
612 views

How to load big geo-data file into web application

I am building a web app where I show details in map. I load data using geojson file (190 mb). I was looking in different possibilities to show the data, here there are: Leaflet GeoJSon: it should ...
2
votes
1answer
112 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
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2answers
3k views

How to label GeoJSON polygons?

I'm using Leaflet combined with GeoJSON features. Is there a way to label GeoJSON features (in this case - polygons)? It should get labels from feature.properties.name This is my code where I ...
2
votes
3answers
647 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
91 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
219 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
169 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
82 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
1answer
1k views

ogr2ogr : Converting KML to GeoJson

I have a requirement convert .HML file to GeoJSON or JSON. Can you please recommend open source command line tools on GNU/Linux(2.6.32-358.14.1.el6.x86_64)? I have installed gdal, I am getting beloow ...
2
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2answers
502 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
1answer
818 views

Converting multilayer KML files to GeoJSON using ogr2ogr

I have a kml file that I'm trying to convert to GeoJSON. However, it turns out there's multiple layers, and ogr2ogr isn't happy. $ ogr2ogr -f GeoJSON shapes.json shapes.kml ERROR 6: GeoJSON driver ...
2
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2answers
867 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
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2answers
322 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
3answers
713 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
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2answers
959 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
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3answers
551 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
2answers
1k 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

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
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
4answers
159 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
73 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
169 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
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2answers
176 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
2k views

Custom marker/icon based on attribute data in leaflet/geojson

I would like to add different icons to my leaflet map based on attribute data. My layer is a geojson layer, it is coming from geoserver with jsnop. I can see my data with the default marker, but when ...
2
votes
1answer
168 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
70 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
93 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
276 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
406 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
263 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 ...
2
votes
1answer
698 views

Converting wkt to geojson with OpenLayers

I am trying to convert wkt to geojson wit OpenLayers. I wrote my code based on this question (geojson to wkt). That's what I have so far, but it is not working. Any ideas? var = ...
2
votes
2answers
425 views

Show different marker for cluster and icon for single vector features in OpenLayers

I have a vector layer which is geoJSON file containing school points and their attributes,to visualize this i defined cluster and show circle which size is based on the number of features it contains. ...
2
votes
2answers
608 views

How do I sort a geoJSON feature collection alphabetically by a property value?

I am trying to sort the objects in a geoJSON FeatureCollection alphabetically by the values of one of their properties. How do I get to the nested object properties with JavaScript? I have tried using ...
2
votes
1answer
131 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
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
176 views

Is it necessary to add Tile layer background?

Is it necessary to add tile layer for making a GeoJSON data rendered in web browser using Leaflet or any other API ? I have a geoJSON data (I obtained the GeoJSON data by converting .shp file to ...
2
votes
2answers
572 views

how we create line between two cordinates on polymap?

I am working on d3 and polymaps, I plot map and create circle on the given latitude and longitude which retrieves from the JSON file but now I want to connect those circles with line. I tried to do it ...
2
votes
2answers
622 views

How can I convert geoJSON data to GPX format

I want to know how I can convert geoJSON data to GPX format.
2
votes
1answer
62 views

How to efficiently use a Postgres DB with Python

I have a Postgres DB with a lot of lines that are too long and so now I want to split those lines into smaller ones. This is why I started writing a little python script for that job. Basically it ...
2
votes
1answer
191 views

Ol3 displaying a vector layer

I have GeoJson that happily displays on GeoJson.IO that I am trying to display on a Vector Layer on an Open Layers 3 Map. The GeoJSON is in EPSG:4326, the Map is in EPSG:3857. My Code is: view = ...
2
votes
1answer
86 views

How to project a GeoJSON on the fly in OpenLayers 3?

I have been trying to load a GeoJSON without success. I have a map with a background layer from OSM. I have some data in 4326 I want to overlay on that map. I do not want to transform coordinates one ...
2
votes
1answer
50 views

Remove null attributes from GeoJSON

I used the following command to reproject a GeoJSON from lat/lon to 3857: ogr2ogr -f "GeoJSON" results_3857.json -t_srs "EPSG:3857" results.json Unexpectedly, the resulting file was 5 times larger ...
2
votes
2answers
214 views

How to query postgres with gis to get GeoJSON for GeoJSON tile layer?

I have a postgres database with one table like the following: CREATE TABLE post_pl ( gid serial NOT NULL, zip character varying(5), zip_n integer, city character varying(50), geom ...
2
votes
1answer
143 views

hiding some “feature”s in GeoJSON file on map

I have geojson file including boundaries of most countries in world. When I clicked on a "feature" (aka country, or polygon) I want to hide it while keep showing the others. because I am planing to ...
2
votes
1answer
51 views

Figuring out what coordinates supposedly using 'NAD31 projection' refer to

I'm working with a GeoJSON file that contains sets of coordinates associated with street corners in the city of Montreal, Canada. The spec sheet of the API delivering those GeoJSON specifies that the ...
2
votes
1answer
507 views

Merge two geojson files

I have a global json files about countries' boundaries but the Russia is in two parts (two polygons). I want to merge the two parts in one, without the boundary at the middle. Is there a way to ...
2
votes
1answer
46 views

How can I see the layers in an .OSM file?

I have an osm file. I am trying to convert it to geojson with ogr2ogr. I get an error that ogr2ogr can't handle multiple layers. How can I tell what layers are in the file and remove them? I see from ...