From ZIPcode+4 to ZIP

[Alessandro Corvasce]

Goodmorning,

I am working with a database that contains the number of crimes in neighborhoods from different cities in the USA.
I have geocoded each crime and I retrieved the ZIPcode for each observation. However, some obs have the ZIP+4 while others (the majority) only have the 5 digit ZIP. How can I delete the +4 part (-####) from the observation containing it in order to have only the 5 digit ZIP code for each obs?
Thank you very much,
ac

[Daniel Shin]

gen g_postcode5=substr(g_postcode,1,5)

[Alessandro Corvasce]

Thank you very much, you have been really helpful