yogi_Extract Partial String (ending at .com) From Cells Of One Column To Cells Of Another Columns

                                          Google Spreadsheet   Post  #1447
Yogi Anand, D.Eng, P.E.      ANAND Enterprises LLC -- Rochester Hills MI     www.energyefficientbuild.com.   Dec-26, 2013
question by Cassidy Price (http://productforums.google.com/forum/?zx=e80jmfn2nptg#!category-topic/docs/spreadsheets/OKEPzLavo8M)
Extract partial string from one cell to another

I want to extract the domain from a list of urls from one column to another. For example;

I want to take this url from column A, e.g.

http://www.philly.com/philly/health/topics/HealthDay683371_20131226_White_House_Extends_Insurance_Enrollment_Deadline_for_Second_Time.html

and extract only the domain name to column B, e.g

http://www.philly.com

So for example, if I have a list of urls in column A:

http://www.philly.com/philly/health/topics/HealthDay683371_20131226_White_House_Extends_Insurance_Enrollment_Deadline_for_Second_Time.html

http://www.cnn.com/2013/12/26/showbiz/doctor-who-christmas-matt-smith-farewell/

http://abcnews.go.com/US/wireStory/friday-power-restored-areas-21337106

I would end up with a list of domains in column B:

www.philly.com

www.cnn.com

abcnews.go.com

Can this be done? I've been trying to figure out a way to use regular expressions to accomplish this but I'm stumped. Thanks for any help!

--------------------------------------------------------------------------------------------------------------------------------------------