assign year and month for missing date

[urban58]

Hello SAS community,

I have the following   

examdate

08/25/2020

09/01/2020

.

.

09/14/2020

10/01/2020

I want to extract year and month, if examdate is missing then year and month variable (newdate)=202009 so I get the following

examdate newdate

08/25/2020 202008

09/01/2020 202009

.                  202009

.                  202009

09/14/2020 202009

10/01/2020 202010

With the following code, I'm able to extract year and month correctly if examdate is NOT missing

data want;
   set have;
newdate = examdate;
if newdate = . then newdate = 202009;
FORMAT newdate yymmn6.;
run;

if examdate is missing, I get the following

examdate newdate

.               251301

.               251301

Can anyone help so I get 202009 instead of 251301.

Thanks in advance,

Margaret 

[Reeza · Accepted solution]

You have to specify dates in a specific format in SAS or use the MDY() function. Both types of date require a day component though you don't need to use it since the format will not display it so just set it to the 1st or 15th as you prefer. 

To specify a date you need to use the DATE9 format.

if newdate = . then newdate = "01Sep2020"d;

or 

if newdate = . then newdate = mdy(9, 1, 2020);

SAS stores dates and times as numbers so when you provide 202009 that's a number that represents a date, SAS does not interpret it September 2020. 

Here's a great, but longer and in depth, reference for dates and times in SAS
https://communities.sas.com/t5/SAS-Communities-Library/Working-with-Dates-and-Times-in-SAS-Tutorial/...

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@urban58 wrote:

Hello SAS community,

I have the following   

examdate

08/25/2020

09/01/2020

.

.

09/14/2020

10/01/2020

I want to extract year and month, if examdate is missing then year and month variable (newdate)=202009 so I get the following

examdate newdate

08/25/2020 202008

09/01/2020 202009

.                  202009

.                  202009

09/14/2020 202009

10/01/2020 202010

With the following code, I'm able to extract year and month correctly if examdate is NOT missing

data want;
   set have;
newdate = examdate;
if newdate = . then newdate = 202009;
FORMAT newdate yymmn6.;
run;

if examdate is missing, I get the following

examdate newdate

.               251301

.               251301

Can anyone help so I get 202009 instead of 251301.

Thanks in advance,

Margaret 

---

[urban58]

Thank you Reeza, that worked perfectly!