Date:         Fri, 22 Nov 2002 17:45:13 -0500
Reply-To:     Paul McDonald <pdm@SPIKEWARE.COM>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Paul McDonald <pdm@SPIKEWARE.COM>
Subject:      Re: Set statement bug?

Paul Dorfman shows some good ideas here!


I've got a suggestion on the first one that I like...


1          /*
2          Imagine you have 3 SAS data sets A1-A3; you want to know which
one has
3          the largest number of records and print that number in the log.
Here is
4          one way of going about it:
5          */
6
7          /* Create a sample data set */
8
9          data a b c ;
10            do i = 1 to 100 ;
11               if i < 25 then output a ;
12               else output b ;
13               output c ;
14            end ;
15         run ;

NOTE: The data set WORK.A has 24 observations and 1 variables.
NOTE: The data set WORK.B has 76 observations and 1 variables.
NOTE: The data set WORK.C has 100 observations and 1 variables.
NOTE: DATA statement used:
      real time           0.05 seconds
      cpu time            0.04 seconds


16
17         /* Paul Dorfman's Method */
18
19         data _null_ ;
20            max = na1 max na2 max na3 ;
21            put max = ;
 2                                                          The SAS
System                            15:27 Friday, November 22, 2002

22            stop ;
23            set a nobs = na1 ;
24            set b nobs = na2 ;
25            set c nobs = na3 ;
26         run ;

max=100
NOTE: DATA statement used:
      real time           0.04 seconds
      cpu time            0.04 seconds


27
28         /* Paul McDonald's Method, using %obscnt macro from stored macro
facility
29
30         %macro obscnt (data) /des='returns number obs from a SAS
dataset' ;
31            %local data data_id rc ;
32
33            %let data_id = %sysfunc(open(&data)) ;
34            %if &data_id %then %do ;
35               %sysfunc(attrn(&data_id, nobs))
36            %end ;
37            %else %do ;
38               %put WARNING: Open for dataset %data(&data) failed ;
39               %put WARNING: Macro OBSCNT will return the number of
observations as missing. ;
40               %put %sysfunc(sysmsg()) ;
41               .
42            %end ;
43            %let rc = %sysfunc(close(&data_id)) ;
44         %mend obscnt ;
45         */
46
47         data _null_ ;
48            max = max(%obscnt(a), %obscnt(b), %obscnt(c)) ;
49            put max = ;
50         run ;

max=100
NOTE: DATA statement used:
      real time           0.06 seconds
      cpu time            0.04 seconds