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Hi Prab,
FIRST. and LAST. processing in the datastep
is very handy. It requires that you have
the dataset sorted and the in your datastep
you add the BY statement to the SET statement.
The BY with the SET automatically creates all
the combinations of first. and last. flags for
each element in the BY statement. Very Handy!
Add a put _all_; to the datastep to
get a visual of all these flags created. By
the way, these flags get set with 0 or 1 for
false or true.
data sample;
input COMP STAND PLOT $ TRANS DIA;
cards;
23 10 1A 1 0
23 10 1A 2 9
23 10 1A 3 0
23 10 1A 4 0
23 10 1A 5 8.5
23 10 1A 6 0
23 10 1A 7 9
23 10 1A 8 0
23 10 1A 9 0
23 10 1A 10 0
23 10 1A 11 0
23 10 1A 12 0
23 10 2A 1 28.5
23 10 2A 2 0
23 10 2A 3 0
23 10 2A 4 0
23 10 2A 5 0
23 10 2A 6 0
23 10 2A 7 0
23 10 2A 8 13
23 10 2A 8 24.5
23 10 3A 1 0
;
run;
proc sort data=sample;
by COMP STAND PLOT TRANS;
run;
data result;
set sample;
by COMP STAND PLOT TRANS;
if first.plot or last.plot then delete;
run;
Hope this is helpful.
Mark Terjeson
Senior Programmer Analyst, IM&R
Russell Investment Group
Russell
Global Leaders in Multi-Manager Investing
-----Original Message-----
From: SAS(r) Discussion [mailto:SAS-L@LISTSERV.UGA.EDU] On Behalf Of
tantrik
Sent: Friday, June 24, 2005 7:47 AM
To: SAS-L@LISTSERV.UGA.EDU
Subject: How to trim 1st and last data in a series?
HI
I have been too addicted to point and click but realized life's not that
easy. I have a dataset like this:
COMP STAND PLOT TRANS DIA
23 10 1A 1 0
23 10 1A 2 9
23 10 1A 3 0
23 10 1A 4 0
23 10 1A 5 8.5
23 10 1A 6 0
23 10 1A 7 9
23 10 1A 8 0
23 10 1A 9 0
23 10 1A 10 0
23 10 1A 11 0
23 10 1A 12 0
23 10 2A 1 28.5
23 10 2A 2 0
23 10 2A 3 0
23 10 2A 4 0
23 10 2A 5 0
23 10 2A 6 0
23 10 2A 7 0
23 10 2A 8 13
23 10 2A 8 24.5
23 10 3A 1 0
so on................................
I want to get rid of the first and the last TRANS in a PLOT because it
is outside the plot boundary. so for Plot 1A, Trans 1 and trans 12 would
be out, for Plot 2A, TRANS 1 and both of the Trans 8 would be out.. How
would I do it? As I mentioned, I hardly know how to spell programming.
Nevertheless, i'm a quick learner and dont mind working loooong hours to
learn including nights and weekends. I appreciate your valuable
suggestions. HAVE A GREAT WEEKEND.
Prab Dahal
Program Technician
University of Arkansas-Monticello
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