Find nearest latitude and longitude points

geolocation

An question on latitude and longitude…Probably a silly one.

I have a set of latitude and longitudes for various locations.And, I have the latitude and longitude of the location in which I am in.

Now,I have to find the nearest places from my locations from the set of latitudes and longitudes I have. Is thee any special way of calculating it or it is just mere subtraction and checking the difference?

Could you please throw some light on this?

Thanks,
J

Best Answer

It depends on how the points are placed.

For example - if most of the points are in a parking lot, then Euclidean Distance should work well.

In other cases - Geodesic Distance needs to be computed. This link should help you with more information.

Here is the conversion from Decimal format to Degree-Minute-Second format and vice versa.

cheers

Related Solutions

Google-maps – Calculate longitude/latitude

This sounds like a basic latitude-longitude triangulation question. The common approaches are outlined in a Yahoo! Answers topic here. There are likely libraries to do this in many languages. A google search for "latitude longitude triangulation" plus your language of choice will likely reveal some existing code to use. "Geocoding" is another common task rolled into similar libraries, so that may be another useful keyword.

Edit: As others have mentioned, "trilateration" seems to be the best term. However, depending on your data and requirements, there are simpler approximation solutions that may satisfy your requirements.

The Yahoo! Answers post is quoted below for convenience:

"For larger distances, spherical geometry. For relatively small ones, treat the earth as flat, and the coordinates as xy coordinates. For the distances to work with the degrees of the coordinates, you will have to use the cosine function to convert from one to the other. (While degrees of latitude are about 69 miles all over the earth, degrees of longitude vary from the same at the equator to 0 at the poles.)

You have the center points of three circles and the radius of those circles. They are supposed to intersect at one point, so you can treat them in pairs to find the intersection points of each and throw out the ones that don't match http://mathworld.wolfram.com/Circle-CircleIntersection.html." (mike1942f)

Android – Get the distance between two geo points

Location loc1 = new Location("");
loc1.setLatitude(lat1);
loc1.setLongitude(lon1);

Location loc2 = new Location("");
loc2.setLatitude(lat2);
loc2.setLongitude(lon2);

float distanceInMeters = loc1.distanceTo(loc2);

Reference: http://developer.android.com/reference/android/location/Location.html#distanceTo(android.location.Location)

Best Answer

Related Solutions

Google-maps – Calculate longitude/latitude

Android – Get the distance between two geo points

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