Incrementing a date by 2 days within a defined period of time

[Lyn2]

Hi-

I'm stuck... I need to identify a sample of records spaced by 2 days beginning on 1 April 1968 and ending on 31 July 1974. My initial approach of taking the days 1,3,5... obviously doesn't work.

My dataset contains the date (SAS format) as well as the month, day and year as individual variables. Ideally I would like the following:

t_date      flag

3/1/1968   1

3/2/1968   0

3/3/1968   1

...

Thank you in advance for your help.

[Ksharp · Accepted solution]

data have;
do date='01mar1968'd to '31jul1974'd;
flag=mod(date+1,2);
 output;
end;
format date date9.;
run;

[Lyn2]

Thank you, this worked perfectly!