01-12-2015 01:49 PM
Given the syntax of WEEK(<sas-date>, <'descriptor'>) for the week function and "U" being Sunday as first day of week and "W" being Monday as first day of week, is it possible to change these or create a custom descriptor to set the start of the week to Saturday? I have a report that I am creating where currently it reports stats on a weekly basis starting on Sunday and running through Saturday. The recipient of the report would like the report to run from Saturday and end on Friday.
01-12-2015 02:19 PM
I found this in a white paper online, initial testing appears to be working for shifting the start of the week for the date ranges.
The quickest way to group weeks with a start date other than Sunday is by using Shift Operators
with the INTNX function. If you recall the first parameter specified in the INTNX function is the
interval. Multipliers and shift indexes can be used with the basic interval names to construct more
complex intervals. When using multipliers and shift indexes your interval name will have the
NAME is the basic interval time. In our case, it would be WEEK
m is an optional multiplier which multiplies the interval by the specified value. For
example, the interval WEEK2 consists of two-week periods.
S is an optional starting point for the interval. By default, the WEEK interval starts on
Sunday with Sunday=1. So if you want a week to start on Wednesday (value =4) then the interval
would be WEEK.4 .
Both the multipliers and shift index are optional and default to 1. So the intervals,
WEEK,WEEK1.1,WEEK.1 are all equivalent to the basic week interval. Different intervals are shifted
by different subperiods. For our purposes, week is shifted by days. Also the shift index cannot be
greater than the number of subperiods in the whole interval (so no greater than 7).
For example, let’s take our last3weeks dataset but define the weeks to start on Thursdays:
DATA last3weeks; SET last3weeks;
start = intnx('week.5',trans_date,0,'beginning'); end = intnx('week.5',trans_date,0,'end');
ThuWeeks = catx(' - ', PUT(start2,mmddyy8.),put(end2,mmddyy8.));