topic Re: Convert Character Date to Numeric (I know this has been asked before) in SAS Programming

Convert Character Date to Numeric (I know this has been asked before)

UdayGuntupalli — Wed, 27 Feb 2019 04:02:55 GMT

All,
I know there are many posts on the community and I tried following the suggestions in these posts without much success. Here is a very relevant post (https://communities.sas.com/t5/SAS-Programming/URGENT-extract-Year-and-Month-from-a-date-variable/td-p/288783) .

Let me show what I have tried to do and my code:

Data Have; 
	Set Work.temp (Keep = UtcReadTime ); 
	Left = scan(UtcReadTime,1,'T');
  	Right = scan(UtcReadTime,2,'T');
  	format Left yymmdd8.; 
  	format Right yymmdd8.; 
  	Date = input(Left,yymmdd8.);
  	Year = Year(Date); 
  	Month = Month(Date); 
  	Day = Day(Date); 
  	Hour = Hour(Right);
Run;

Re: Convert Character Date to Numeric (I know this has been asked before)

UdayGuntupalli — Wed, 27 Feb 2019 04:33:24 GMT

This seems to work, but I am curious as to why my previous approach does not work :

Data Have; 
	Set Work.sitepvforecast (Keep = UtcReadTime ); 
	Left = scan(UtcReadTime,1,'T');
  	Right = scan(UtcReadTime,2,'T');
  	Year = substr(Left,1,4);
  	Year_n = input(Year, best12.);
  	Month = substr(Left,6,2); 
  	Month_n = input(Month,best12.); 
  	Day = substr(Left,9,2);
  	Day_n = input(Day,best12.);
  	Hour = substr(Right,1,2);
  	Hour_n = input(Hour,best12.); 
Run;

Re: Convert Character Date to Numeric (I know this has been asked before)

PGStats — Wed, 27 Feb 2019 04:45:27 GMT

SAS functions YEAR, MONTH, DAY, etc. work on SAS dates which are numbers. You were applying them to character strings.

204  data _null_;
205  t = today();
206  y = year(t);
207  m = month(t);
208  d = day(t);
209  str = put(t, yymmdd10.);
210  put (_all_) (=);
211  run;

t=21606 y=2019 m=2 d=26 str=2019-02-26

Re: Convert Character Date to Numeric (I know this has been asked before)

UdayGuntupalli — Wed, 27 Feb 2019 04:54:26 GMT

@PGStats ,
Thank you for your response. If you look at the link that I posted, the solution achieved in that discussion also goes through a similar set of steps.

If your source variable is CHARACTER then you need to make a NEW variable if want to store it as an actual date value.

data want ;
  set have ;
  first_chemo_date_num=input(first_chemo_date,yymmdd8.);
  format first_chemo_date_num yymmddn8.;
  yr=year(first_chemo_date_num);
  mth=month(first_chemo_date_num);
run;

I understand that I am starting of with a character, however I thought the input function was supposed to cast it into a numeric date as explained in this example and that is what I tried. Just to be clear, besides the example code I posted, I also tried creating a new variable exactly as shown .

Re: Convert Character Date to Numeric (I know this has been asked before)

PGStats — Wed, 27 Feb 2019 05:28:12 GMT

The only problem with your code was the width of the informat. By asking yymmdd8. you were missing the last two characters of the date part of the string. Look:

218  data _null_;
219  str = "2019-02-27T04:00:00";
220  date = input(str, yymmdd10.);
221  format date yymmddn8.;
222  put (_all_) (=);
223  run;

str=2019-02-27T04:00:00 date=20190227