0
votes
0answers
12 views

Dot density inside polygon (kml co-ordinates)

I have a kmz url(its not in local), which has so many polygons in it. Which contains co-ordinates something like: <LinearRing> <coordinates>138.878021,-34.971903,0.0 ...
1
vote
0answers
30 views

How to dissolve inner polygons in a multipolygon

I'm trying to get the boundary of a collection of zip codes. Here is my current sql: SELECT ST_AsText(ST_SimplifyPreserveTopology((ST_Union(geom)), .003)) as poly FROM zcta5_data WHERE zcta5 IN ...
0
votes
3answers
156 views

ST_transform postgis

SQL within that zone is a point SELECT "public".zona.zts FROM "public".zona WHERE ST_Within ( ST_Transform ( ST_GeomFromText ( 'POINT(-30.033514 ...
0
votes
1answer
62 views

Searching closest region from Google Maps coordinates

Here is my problem. I'm mapping a region in google maps after that I'm saving the coordinates in PostGIS databse as geographic Polygon type. ST_GeographyFromText('SRID=4326;POLYGON((..))') The goal ...
0
votes
1answer
388 views

How to use Google Maps projection with GeoDjango/PostGIS

I am building a web service with GeoDjango which involves user submitted events including a location. I created a model field for my location using django.contrib.gis.db: location = ...
2
votes
0answers
96 views

how do I create a RESTful PostGIS web Service Framework?

I have PostGIS tables that store vectors that want to show on Google Maps. Read the post http://gis.stackexchange.com/questions/22354/how-to-display-a-postgis-table-on-google-maps But one thing that ...
2
votes
1answer
368 views

How to save a google map direction into a postgresql/postgis database?

I have taken a direction(route) from google map. Can I save this resultant direction/path/route to my postgresql/postgis database? How?
0
votes
2answers
916 views

How to install PostGIS and OpenLayers plugins?

I am new to QGIS and have installed the QGIS v 2.2.0. For adding google map as a base layer I need to install OpenLayers plugin. I also need to add the PostGIS plugin for DB management purpose. Can ...
0
votes
1answer
44 views

Is it possible to render POIs/landmarks from Postgres/postgis DB using google Map like icons?

Is it possible to render POIs/landmarks from Postgres/postgis DB using google Map like icons? Any readily available icon sets?
-1
votes
1answer
758 views

Retrive data from database in openlayer GIS

i am using this code but it shows nothing, whats wrong with this code. <!DOCTYPE html> <html lang='en'> <?php $conn_string = "host=localhost dbname=postgis_21 user=postgres ...
2
votes
1answer
561 views

Postgis | Problems Reprojecting a Point from UTM ED50 to GEOGRAPHIC ETRS89

I've got a POINTS PostGIS table in the 23030 (ED50 UTM 30N) SRID. I'm having a lot of problems trying to reproject those points from ED50 UTM coordinate system to ETRS89 Geographic (lat/long) ...
1
vote
2answers
945 views

Attempting to use ST_DWithin to locate objects within a given distance of meters using SRID 4326

I'm a Rails developer with minimal GIS experience, working with PostGIS and the RGeo gem. I'd like to find all of the cows within 500 meters of my current location. So, I'll create a model for my ...
3
votes
1answer
357 views

How do I find the intersection of two polylines in PostGIS?

I have a set of road conditions reported for small segments of road, and I am hoping to determine the specific subset of each segment which intersect with a route along the road so that I can draw the ...
3
votes
3answers
348 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 ...
1
vote
1answer
201 views

Shortest path for a given waypoints

I have an application where the user selects some "markers" from a google maps (all those coordinates' markers are stored into a postgresql database). Right now, I can draw the route between all ...
3
votes
2answers
734 views

Rendering geoJson polygons in google maps android apiv2

I'm in the process of publishing spatial data stored in a postgis database to a google maps based android app and am trying to put together a plan for rendering my data in the most efficient manner ...
1
vote
4answers
703 views

How do I stop the map at just one world/globe?

I am working on a project to put google maps layer and adding our data layers on top of it. using openlayers and google maps layer with out layer of top of it now the google layer has max resolution ...
0
votes
1answer
362 views

What Spatial Reference System do I store Google Map's Lat/Lng in [duplicate]

I am new to PostGIS, Spatial Reference Systems and projections and want to store lat/lng coordinates retrieved from Google Maps and its services like the Geocoder. I'm working with data in America and ...
8
votes
1answer
858 views

Generating Heatmap from PostGIS

I have GIS data in a PostGIS data base and would like to generate a density map and display them on a Leaflet/Google Maps. Question: What is the recommended/typical method for doing so, without ...
3
votes
1answer
585 views

Routing with multiple points

I am using postgreSQL, postGIS and pgrouting. Now I am really confused on how am I going to find the shortest path between multiple points. I know how to find it between two points through dijkstra ...
2
votes
1answer
135 views

St_buffer width issues

I am using postgres with postgis for spatial data and ArcGIS for visualisation. I am really confused regarding what units the st buffer function uses because when I insert just the value 1 as ...
0
votes
1answer
114 views

How to use bbox in long/lat with google/bing/etc… using mapserver‏

The bbox of OpenLayers.Control.GetFeature works in utm when the baselayer is 900913 ie. google/bing/etc) and in long/lat when the baselayer is 4326 (ie. my postgis layers served by mapserver), no ...
0
votes
1answer
2k views

How to export data from QGIS to display in Google Maps?

I'm exporting layers of a project for a quantum gis postgis table and visualizing the data in gmaps, but the coordinates are very wrong. is there any special way to export the quantum gis? postgres ...
2
votes
1answer
1k views

How to insert google maps lat/lng into postgis in geometry datatype

I came across: https://developers.google.com/maps/articles/phpsqlinfo_v3 I've changed the code a bit and all process is well done for postgis database. I get the data from infobox when user clicked. ...
2
votes
2answers
394 views

How to pull lat/lng from a map canvas and update a database

So if i want to pull out lat/lngs after user clicks on a map canvas (lat/lngs are pulled using any javascript API (leaflet, wax etc.) and add this to a postgresql database using a query, how do i do ...
2
votes
1answer
199 views

Simple GIS to Provide Urban Boundaries

I have an app built on top of Google Maps right now and everything works great. I want to add one feature that seems exceedingly difficult. On my site, I want users to be able to type "Boston, MA" or ...
5
votes
1answer
413 views

GIS-based reporting and maintenance tool

Background Conceptually, I am looking for a tool, or suite of software tools that can be readily integrated to help browse data using a GIS-based map (such as Google Maps). The proposed architecture ...
1
vote
1answer
3k views

Google Maps MarkerClusterer - Remove all clusters

So, I have a PostGreSQL DB with 317 datapoints - all spatially enabled through PostGIS. I have queried this using PHP as GeoJSON and overlaid it on Google Maps (using a converting routine). I have ...
7
votes
1answer
2k views

Output polygon data from postGIS and read it on Google Maps API

So, I have a group of polygons stored in PostGIS. I'm trying to build a web application with Google Base maps (using Google Maps API). Now, How do i output the polygons in the right format so that ...
4
votes
2answers
4k views

How to display a PostGIS table on Google maps?

I am attempting to take a shape file and display it on a map: I can do something like this: SELECT ST_AsText((ST_Dump(the_geom)).geom) as the_geom FROM shapes; But the problem is I still have to ...
3
votes
1answer
399 views

making choropleth maps using PostGIS Windows

i read an article on chicago tribune blog about making maps, it consist on "making choropleth maps using PostGIS, TileMill, Mapnik and Google Maps" on Mac environnement, my question is how we can ...
6
votes
4answers
2k views

Point in polygon algorithm for multiple polygons

I've a Google map with bunch of polygons on it. Here is a problem I'm interested in: Given a lat,lng point, what's the best way to determine all the polygons that this point lies in? The obvious way ...
10
votes
1answer
950 views

Can you query overlapping user-defined polygons at a given point in Google Maps?

I need to find out the limitation of working with the Google Maps API, and the possible solutions for doing semi-complex spatial comparisons. What I'm looking to achieve is a system of comparison ...
3
votes
1answer
224 views

Unexpected Result After Reprojection Attempt

I'm a member of a student team that is currently researching how to query raster information using PostGIS v2.0. Our raster's coordinate system is EPSG 2236 (NAD 83 / Florida East) and as we will be ...
2
votes
1answer
2k views

Add a polygon to PostGis from Google Maps

i have some experience with Google maps api, I have an app and currently calculate nearest points to locations via distance functions (great circle) and having a lot of waypoints on MySQL. I want to ...