How to assign field name area_code to first 3 digits in voip logs and geolocate based on field?

[hartfoml]

My voip logs have a format of xxxxxxxxxx 10 digit number.

Two questions:

How do I assign a field name of "area_code" to the first 3 digits of the number?

How do I do a geolocate on the area_code?

Thanks in advance for your help

[somesoni2 · Accepted solution]

For first one you can use calculated fields.
http://docs.splunk.com/Documentation/Splunk/6.1.2/Knowledge/definecalcfields

May be this one for the second

http://apps.splunk.com/app/1515/