topic Re: Changing the date for one observation: date format MMDDYY8. in SAS Programming

Changing the date for one observation: date format MMDDYY8.

Emma_at_SAS — Tue, 22 Jun 2021 16:22:41 GMT

I have a Date column that is numeric with format MMDDYY8. I want to modify one of the dates in my dataset. I tried the following code to change the date for a specific ID participant:

data want;

set have;

if IDvar eq "ABCD" then datevar = 03/08/20;

run;

Type

Format

Num

MMDDYY8.

but instead of the date I want, I got 01/01/60

01/01/60

May you please help me solve this?

Thanks!

Re: Changing the date for one observation: date format MMDDYY8.

Reeza — Tue, 22 Jun 2021 16:28:03 GMT

You need to provide dates in a specific format, "08Mar2020"d -> I would always recommend using a 4 digit year as well.

if idvar = 'ABCD" then datevar = '08Mar2020'd;

Jump to the section on Dates/DateTimes here:
https://documentation.sas.com/doc/en/pgmsascdc/9.4_3.5/lrcon/p0cq7f0icfjr8vn19vyunwmmsl7m.htm

Re: Changing the date for one observation: date format MMDDYY8.

PaigeMiller — Tue, 22 Jun 2021 16:28:08 GMT

You are close. Here is the way to do this:

if IDvar eq "ABCD" then datevar = '03AUG2020'd;

It has to be that exact syntax, except that it can be upper or lower or mixed case.

Re: Changing the date for one observation: date format MMDDYY8.

Tom — Tue, 22 Jun 2021 16:45:20 GMT

3 divided by 8 divided by 20 is 0.01875 which is less than 1. So 01JAN1960 is the right date for the value you stored.

Did you intend to set the date to the 08MAR2020? Or perhaps 08MAR1920?

If so then you can either use a date literal (a quoted string that the DATE informat can read followed by the letter d) or a function that returns that date or the actual date value of 21982.

datevar = '08mar2020'd;
datevar = "8MAR2020"d;
datevar = '01-mar-2020'd;
datevar = mdy(3,8,2020);
datevar = 21982 ;

Re: Changing the date for one observation: date format MMDDYY8.

Emma_at_SAS — Tue, 22 Jun 2021 16:49:07 GMT

Thank you, Reeza, PaigeMiller, and Tom. All your answers were very helpful and I learned from each response.

Thanks!

Re: Changing the date for one observation: date format MMDDYY8.

PaigeMiller — Tue, 22 Jun 2021 16:55:42 GMT

Hello @Emma_at_SAS

I'm glad you got an answer you can use.

If can make a suggestion, from now on you'd be better off using 4 digit years, rather than 2 digit years. This will avoid complications and confusion at some point in your programming career.

Re: Changing the date for one observation: date format MMDDYY8.

Emma_at_SAS — Tue, 22 Jun 2021 18:21:34 GMT

Thank you, PaigeMiller! I very much appreciate your advice! I agree that is great advice and I will follow that!

Re: Changing the date for one observation: date format MMDDYY8.

Emma_at_SAS — Tue, 22 Jun 2021 18:25:36 GMT

Tom, may I ask how you calculated 21982?
Thanks!

Re: Changing the date for one observation: date format MMDDYY8.

Tom — Tue, 22 Jun 2021 18:27:58 GMT

@Emma_at_SAS wrote:
Tom, may I ask how you calculated 21982?
Thanks!

Just ask SAS to show you.

208   data test;
209     x=mdy(3,8,20);
210     put x=;
211   run;

x=21982

Re: Changing the date for one observation: date format MMDDYY8.

Emma_at_SAS — Tue, 22 Jun 2021 18:28:49 GMT

Great! Thanks!