lat-long

UTM and MGRS to Latitude/Longitude conversion source-code?

What open-source / public domain software is there "out there" for conversion between Latitude/Longitude, UTM (Universal Transform Mercator) and MGRS (Military Grid Reference System)? We're using a VB6 library at the moment and would prefer to use something in another language and with a longer pedigree. ...

Clustering Lat/Longs in a Database

Hi folks, I'm trying to see if anyone knows how to cluster some Lat/Long results, using a database, to reduce the number of results sent over the wire to the application. There are a number of resources about how to cluster, either on the client side OR in the server (application) side .. but not in the database side :( This is a simi...

How can I convert UTM coordinates from Meters to Feet?

Does anyone have a formula or conversion that will switch my UTM coordinates from Meters to Feet? I found Javascript code that will convert UTM coords in meters to Lat/Long but I will need my UTM in feet before I convert it to Lat/Long. Thanks, ...

Query points using SQL Server 2008 geography type

I have a table with the geography type and I want to run a query to find all rows within 25 miles of a specific lat/long. What would the query look like to accomplish this? ...

Trilateration using 3 latitude and longitude points, and 3 distances

There exists an unknown target location (latitude and longitude co-ordinates). I have 3 latitude and longitude co-ordinate pairs and for each pair a distance in kilometers to the target location. How can I calculate the co-ordinates of the target location? For example, say I have the following data points 37.418436,-121.963477 0.2657...

Data structure with two primary keys? (caching lat/lon address pairs)

I'm trying to cache lat/lon address pairs from Google Maps, so I need a data structure where the key is two ints (lat and lon). What's the simplest data structure for that? I thought of two ways so far: Nested hash: {37.734608 {-121.913019 "San Ramon, CA" -121.6 "Tracy, CA"}} Concat the two to make the key: {"37.734608,-121.913019"...