topic Re: Construct the new variable date in New SAS User

Construct the new variable date

kngu022 — Thu, 23 Jan 2020 14:51:20 GMT

I am creating the new variable - date. I am not too sure what is wrong when the age comes out quite strange.

DATA Date;
	INPUT month 1-2 year 4-7 day 9-10;
	bday=MDY(month,day,year);
	age=INT(MDY(1,1,2008)-bday/365.25);
CARDS;
6  1918 12
7  1948 11
1  1960  1
10 1970 15 
12 1971 10 
;
RUN;
ODS RTF FILE="/folders/myfolders/Lecture_ Resources/Chapter4/Chap4p25";
PROC PRINT DATA=Date;
	FORMAT bday date9. age;
RUN;
ODS RTF CLOSE;

Can anyone tell me what 's wrong with my code?

Re: Construct the new variable date

novinosrin — Thu, 23 Jan 2020 14:59:31 GMT

Plz check the parenthesis

Here is a correction

	age=INT((MDY(1,1,2008)-bday)/365.25);

Re: Construct the new variable date

data_null__ — Thu, 23 Jan 2020 15:00:10 GMT

Order of operations.

age=INT((MDY(1,1,2008)-bday)/365.25);

Re: Construct the new variable date

PaigeMiller — Thu, 23 Jan 2020 15:00:29 GMT

You have made a math error, which extra parentheses will fix.

age=INT((MDY(1,1,2008)-bday)/365.25);

By the way, a better method of accounting for leap years is the INTCK function, or the YRDIF function.

Re: Construct the new variable date

AhmedAl_Attar — Thu, 23 Jan 2020 15:05:50 GMT

Try this data step

DATA Date;
	INPUT month 1-2 year 4-7 day 9-10;
	age=intck('year', MDY(month,day,year), MDY(1,1,2008));
CARDS;
6  1918 12
7  1948 11
1  1960  1
10 1970 15 
12 1971 10 
;
RUN;

Hope this helps,

Ahmed

Re: Construct the new variable date

kngu022 — Thu, 23 Jan 2020 15:41:36 GMT

After changed the code as above, the result comes out still the same. I doubt that my code still has some errors. Could you please show

me please?

DATA dates;
    INPUT  month 1-2 year 4-7 day 9-10;
    bday=MDY(month,day,year);
	age=intck('year', MDY(month,day,year), MDY(1,1,2008));
	
CARDS;
 6   18	12
 6 1918 12
 7 1948 11
 1 1960  1
10 1970 15
12 1971 10
;
RUN;
ODS RTF FILE="/folders/myfolders/Lecture_ Resources/Chapter4/Chap4p25";
PROC PRINT DATA=Date;
	FORMAT bday date8. age;
RUN;
ODS RTF CLOSE;

Re: Construct the new variable date

PaigeMiller — Thu, 23 Jan 2020 20:01:46 GMT

When I run the code you just showed with INTCK, I get meaningful age values, and I do not get the values you show.

I believe you have committed a typing error, and your PROC PRINT should be

PROC PRINT DATA=Dates; /* <== note the S on the end is needed here */

Re: Construct the new variable date

Patrick — Fri, 24 Jan 2020 02:40:04 GMT

@kngu022

In regards of calculating age: Why not use the YRDIF() function which specifically provides an argument to calculate the age.

From the docu found here:

Example 2: Calculating a Person’s Age
You can calculate a person’s age by using three arguments in the YRDIF function. The third argument, basis, must have a value of AGE:

data _null_;
   sdate='16oct1998'd;
   edate='16feb2010'd;
   age=yrdif(sdate, edate, 'AGE');
   put age= 'years';
run;

Re: Construct the new variable date

Tom — Fri, 24 Jan 2020 03:26:10 GMT

Your code is printing a different dataset than the data step is creating.

DATA dates;
...
PROC PRINT DATA=Date;