topic Re: add day to datetime in SAS Programming

add day to datetime

radhikaa4 — Fri, 15 May 2020 20:38:21 GMT

I have one datetime variable and I would like to add 7 days to the existing date/time

patientID	raw_start_date_time	new_start_date-time
1	12/4/2019 15:21 PM	12/5/2019 15:21 PM
2	12/5/19 12:42 PM	12/12/19 12:42 PM

I did the following and didn't work

new_start_date = intck ('dtday', raw_start_date_time, 7)

I also tried intck('day'), intnx ('day'), and raw_start_date_time * 7 * 24 * 60 * 60.

No luck

Re: add day to datetime

Reeza — Fri, 15 May 2020 20:43:49 GMT

INTNX, not INTCK() and dtDAY since you have a datetime.

new_start_date = intnx('dtday', raw_start_date_time, 7);

If you wanted to do it manually you need to ADD that date amount, not multiply it.

 raw_start_date_time  +  7 * 24 * 60 * 60

Re: add day to datetime

Tom — Fri, 15 May 2020 20:43:47 GMT

INTCK() counts intervals. You want INTNX().

Also are variables really datetime and not string? I don't think SAS has a format to display datetime values in that style you are showing. But perhaps that is data you typed into Excel instead?

Re: add day to datetime

Peter_C — Fri, 01 Oct 2021 19:01:14 GMT

New = raw+ 7 *24*3600 ;
A SAS datetime value is an integer number of seconds.
There are 3600 seconds in each of the 24 hours in a day