Google Maps Questions

Rails
1

Hi,

Ive used this link to create google maps in my rails app. I have a few
questions.

This example uses a US Geocoder to find the latitude and Longtitude of
an address.
Is there 1 available for the UK from google or any other service thats
free?

I takes a couple of seconds to get the latitude and longitude from the
geocoder, is it better to hold the latitude and longtitude in the
database?
Does anyone know where i can find a UK website that will provide me with
the latitude and longtitude of a UK address?

Ive looked around the internet and streetmap.co.uk gives you the
latitude & Longtitude for a particular postcode, not the exact address.

Any suggestions would be gretfull.

2

There is no data on precise co-ordinates of individual addresses, but
post codes are pretty accurate… average of 13 addresses per postcode
as far as I can remember.

A good place to go for co-ordinates is here:

You can list the postcodes seperated by commas as I’ve shown, and it
gives you a nice XML output of postcodes with their co-ordinates.

3

yes on the question to store the lat and long in the database. that way,
geocode is executed once instead of everytime someone accesses the
google map.

John B. wrote:

Hi,

Ive used this link to create google maps in my rails app. I have a few
questions.

This example uses a US Geocoder to find the latitude and Longtitude of
an address.
Is there 1 available for the UK from google or any other service thats
free?

I takes a couple of seconds to get the latitude and longitude from the
geocoder, is it better to hold the latitude and longtitude in the
database?
Does anyone know where i can find a UK website that will provide me with
the latitude and longtitude of a UK address?

Ive looked around the internet and streetmap.co.uk gives you the
latitude & Longtitude for a particular postcode, not the exact address.

Any suggestions would be gretfull.

4

koloa wrote:

yes on the question to store the lat and long in the database. that way,
geocode is executed once instead of everytime someone accesses the
google map.

I run a cron job to populate the database with geocode info every night,
that way data can be added to the database without the potential lag of
a geocode lookup. Any record that doesn’t have long/lat fields does a
geocode api query .

5

Chris L. wrote:

koloa wrote:

yes on the question to store the lat and long in the database. that way,
geocode is executed once instead of everytime someone accesses the
google map.

I run a cron job to populate the database with geocode info every night,
that way data can be added to the database without the potential lag of
a geocode lookup. Any record that doesn’t have long/lat fields does a
geocode api query .

Both Yahoo and Google offer Geocoding. Give those a shot.

http://developer.yahoo.com/maps/rest/V1/geocode.html
http://www.google.com/apis/maps/documentation/

6

John B. wrote:

Is there 1 available for the UK from google or any other service thats
free?

There is a duscussion about UK codes here http://drupal.org/node/19482

Try these links as well
http://gabriel.gironda.org/articles/2005/12/01/geolocation-in-ruby-on-rails
http://www.onrails.org/articles/2006/06/01/geoip-data

If you have a decent budget, the data can be purchased
http://www.datadepot.co.uk/dept.asp?level=2&id=2250