Count variable value changes

[Madhav4114]

Help me find solutions for below problem
Date. Newkey. Flag
Dec16. 13. 0
Jan17. 13. 1
Feb17. 13. 1
Mar17. 13. 1


Need to find total cases as to how many times the flag switched from 0 to 1 in above table

[PeterClemmensen]

What does your desired result look like?

[RW9]

Not tested (pop test data in the form of a data step please):

data want;
  set have;
  retain num_times 0;
  if lag(flag)=0 and flag=1 then num_times=sum(num_times,1);
run;

Last record would have your total number of times.  You could also do it via sql to join lowest previous date to current record as well.

[PaigeMiller]

Please go back to your ORIGINAL post and provide a subject line that describes the problem. A subject line of "SAS Code" could apply to 99% of the posts here, and so has no value in describing the problem. Help us out, please; we're trying to help you.

[s_lassen]

If you just need the count, you can do like this:

data want;
  retain count -1; /* the first record should set count to 0 */
  set have end=done;
  by flag notsorted;
  count+first.flag;
  if done;
  keep count;
run;