Dates and Times SAS Date, Time and Date- Time Formats

Date Storage SAS stores Dates, Times and Date-Time values differently. Datetime: seconds between January 1, 1960 and an hour/minute/second within a specified date Time: seconds since midnight of the current day Date: days between January 1, 1960, and a specified date

Functions Functions that extract dates and times from datetime variables DATEPART(variable): extracts the date from a SAS datetime value TIMEPART(variable): extracts the time from a SAS datetime value

Creating datetime variables Functions can convert numeric values to datetime values MDY(month,day,year) gives a date value birthday=mdy(8,27,90); HMS(hour,minute,second) hrid=hms(12,45,10);

Current Dates and Times The following functions extract current values DATETIME() DATE() TIME() These functions have no arguments

Parts of date Values Return numeric values from date values DAY(date) MONTH(date) YEAR(date) WEEKDAY(date) QTR(date)

Parts of time or datetime values HOUR( ) MINUTE( ) SECOND( )

PUT and INPUT functions PUT(source, format.) creates a character value Source can be any format Format must be the same type as the source INPUT(source, informat.) creates a value based on the informat Source is a character expression ? or ?? suppress error messages in the log Informat you want to apply

Examples Character to numeric Sale= INPUT(‘2,115,353’,comma9.) Converting to character Data Test; dateval= put(123456,mmddyy8.); put dateval; run; Produces 01/04/98 in the SAS log

Formats and Informats Formats describe the way variables are written Always contain a period Start with a $ if the variable being modified is character, not otherwise Informats describe the way variables are read Always contain a period Start with a $ if the variable is to be stored as character Formats and informats generally have the same syntax most formats are also informats and vice-versa

Useful datetime formats DATEw. writes date values in the form ddmmmyy or ddmmmyyyy DATETIMEw.d writes datetime values in the form ddmmmyy:hh:mm:ss.ss Note: what is printed depends on the w value DOWNAMEw. writes date values as the name of the day of the week WORDDATEw. writes date values in words Etc. There are many more useful formats.