topic Re: SAS date field in SAS Programming

SAS date field

mmaximos — Wed, 20 Jul 2022 01:00:10 GMT

I have a variable that I've named time_period which contains dates listed in the following format as a numeric variable:

SAS reads these as a "SAS date" and therefore converts 201511 (which is intended to be Nov 2015) to Sep 20, 2511.

I found this out when I tried formatting to a word date so I can understand how SAS was reading it:

data mydata; 
	set sample;
    sasdate=input(time_period, YYMON.); /*YYMMDDw.*/
    format sasdate worddate12.;
run;

From what I understand, I need to take this numeric value and convert it to a date value. Some responses explain that you need to ad an "01" in the code to act as a "dd", so I tried the following:

data cdiff.date;
set cdiff.c;
format sasdate date9.;
sasdate = input(time_period !! "01", yymmdd8.);
run;

This did not work, the output is "." down the entire column.

Other examples suggest adding a specific date in the date field (I think), but that replaces all the dates with this specific date in my new column.

I am not sure how to approach this.

Thanks

Re: SAS date field

mkeintz — Wed, 20 Jul 2022 01:14:39 GMT

I don't think operators (like !!) are allow in arguments to the INPUT function, but the CATS function is. Use

  sasdate=input(cats(time_period,'01'),yymmdd8.);

Re: SAS date field

mmaximos — Wed, 20 Jul 2022 01:18:24 GMT

You are absolutely brilliant, this is exactly what I needed. Thank you!

Re: SAS date field

Tom — Wed, 20 Jul 2022 05:51:05 GMT

If you have numbers like 201,511 and you want to convert that to the date 01NOV2015 there are a number of ways.

You could use arithmetic to extract the YEAR and MONTH values.

date = mdy(int(number/100),1,mod(number,100));

You could convert the number to a string and use the YYMMN informat to convert it.

date=input(put(number,z6.),yymmn6.);

Once you have a date value attach any date type format you want to display it in a way that humans can understand, preferably one that will not be confused for a number like the 201,511 you started with.

Re: SAS date field

ballardw — Wed, 20 Jul 2022 14:20:09 GMT

Possibly go back to your step where you read the data into SAS and read that variable with the YYMMN. informat at the beginning so the value starts as a date. The YYMMN. informat will treat the resulting date as the first day of the month.

data example;
   input date :yymmn.;
   format date yymmdd10.;
datalines;
201511
201511
201612
201701
201701
;