if else嵌套吧，满足了就跳出来，尽量别做所有的判断

7# soporaeternus

谢谢你的意见。
如果我们有1000个变量或者更多的话，用 IF ELSE 会不会很麻烦。
我们知道可以用 IN OPERATOR 去判断一个变量是否等于多个不同的值。
如果也有函数可以运用在这里就好了。

More efficient way turns out much slower than a seemingly dumb approach(3 times faster). It is faster in coding not in executing. See the log below.

753  data t1;
754  array A(100);
755    do i=1 to 1e6;
756      do j=1 to dim(A);
757        A[j]=ceil(ranuni(123)*1000);
758      end;
759      output;
760    end;
761    keep A:;
762  run;
NOTE: The data set WORK.T1 has 1000000 observations and 100 variables.
NOTE: DATA statement used (Total process time):
      real time           13.22 seconds
      cpu time            9.90 seconds

763
764  %macro ifcondition(k);
765    %do i=1 %to &k;
766      %if &i=1 %then A&i=1;
767      %else OR A&i=1;
768    %end;
769  %mend;
770
771
772  data _null_;
773    set t1;
774    if %ifcondition(100)
775    THEN DUMMAY = 1;
776    ELSE DUMMAY = 0;
777  run;
NOTE: There were 1000000 observations read from the data set WORK.T1.
NOTE: DATA statement used (Total process time):
      real time           0.99 seconds
      cpu time            0.63 seconds

778
779
780  data _null_;
781    set t1;
782    ARRAY ARRAY_TEMP {*} A1 - A100;
783    DUMMAY = 0;
784    DO i = 1 TO 100 WHILE (DUMMAY = 0);
785    IF ARRAY_TEMP {i} = 1 THEN DUMMAY = 1;
786    END;
787  run;
NOTE: There were 1000000 observations read from the data set WORK.T1.
NOTE: DATA statement used (Total process time):
      real time           2.23 seconds
      cpu time            1.74 seconds

9# bobguy


Thank you so much.