topic Re: Computing A New Column in SAS Programming

Computing A New Column

EM_G — Tue, 30 Mar 2021 05:32:40 GMT

I'm a new SAS 9.4 user, trying to compute a new column using a IF-THEN statement. The below table is my weather data, the column I am trying to compute is season, for example under the column name Season; from the 1st of Sep 2017 to 30th of November 2017 from the date column will also appear under Season as Spring17.

Below is an unsuccessful attempt.

Re: Computing A New Column

ChrisNZ — Tue, 30 Mar 2021 06:54:11 GMT

Like this:

if '01jan2020'd < DATE < '31mar2020'd then SEASON='Winter2020';

Re: Computing A New Column

Shmuel — Tue, 30 Mar 2021 09:05:41 GMT

Alternative way to assign value to season is by checking the month:

data want;
 set have;
      length season $8;
       mm = month(date);
       if 03 le mm le 05 then season = 'Automn'; else
       if 06 le mm le 08 then season = 'Winter' ; else
       if 09 le mm le 11 then season = 'Spring'; else
       if mm in (01 02 12) then season = 'Summer';
       season = cat(season, put(date,year2.));
run;

Re: Computing A New Column

EM_G — Thu, 01 Apr 2021 02:47:44 GMT

I like this solution, but the trouble is I have three different years and need to be able to identify them in season also. By checking the month only I will have three summers etc. Can I specify year also?

Re: Computing A New Column

EM_G — Thu, 01 Apr 2021 03:44:51 GMT

This worked thank you.

I just had to add an = after both < to include both the first and last date in that season.

Thanks again, great help.

Re: Computing A New Column

Shmuel — Thu, 01 Apr 2021 04:55:03 GMT

@EM_G wrote:

I like this solution, but the trouble is I have three different years and need to be able to identify them in season also. By checking the month only I will have three summers etc. Can I specify year also?

You missed the line where I concatenate the year to the season derived from the month format:

season = cat(season, put(date,year2.));

and, of course, you can replace the year2. format with year4. format, if preferd.

Thus you are free to work with any year and any number of years.

Re: Computing A New Column

EM_G — Thu, 01 Apr 2021 06:03:34 GMT

My apologies, I didn't realize how that worked. I understand now and this works also, so thank you.