st: RE: How do I drop fist and last observations please?

["Sarah Edgington" <sedging@ucla.edu>]

.
That would need to be  drop if inlist(_n,1,_N)
_N-1 is the penultimate observation not the last one.

-Sarah

-----Original Message-----
From: owner-statalist@hsphsun2.harvard.edu
[mailto:owner-statalist@hsphsun2.harvard.edu] On Behalf Of Lance Erickson
Sent: Monday, July 18, 2011 11:59 AM
To: statalist@hsphsun2.harvard.edu
Subject: st: How do I drop fist and last observations please?

I believe the following should work...

drop if inlist(_n,1,_N-1)

Lance


-----Original Message-----
From: owner-statalist@hsphsun2.harvard.edu
[mailto:owner-statalist@hsphsun2.harvard.edu] On Behalf Of Lucie Vlach
Sent: Monday, July 18, 2011 12:38 PM
To: statalist@hsphsun2.harvard.edu
Subject: st: How do I drop fist and last observations please?

Hello everyone!

I need to drop my first and last observation from a data set in a do file.
Not all datasets will have the same number of observations. Is there a good
'drop' command that will do this for me, regardless how long my dataset is?
It will always be the first and last observation.

Here is the example of my data:

Record_Type Sub_Prefix Current_Yr Source Sequence_Number Check_Digit
Transaction_Type Segment_Type Segment_Sequence Action_Code Unused Claim_Type
Service_Provider_ULI Skill_Code Service_Recipient_ULI
2 UCM 00 00 80
3 UCM 11 00 00546733 4 CIP1 CIB1 0001C   RGLR 3535446208 PSYC 352543330
3 UCM 11 00 0037920 6 CIP1 CIB1 0001A   RGLR 2296454208 GP 445454551
4 UCM 00 00 8000143 0 0000 144

Here I want to drop: "2 UCM 00 00 80" and "4 UCM 00 00 8000143 0 0000 144"

Thank you all very much for any help!

Lucie

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