SAS Date,Time and datetime functions

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A Beginners Guide to SAS Date and Time Handling:

Abstract:

The SAS system provides a plethora of methods to handle date and time values. Correct date
computation became a very important subject when the world became aware of the Year 2000 issue. Computer users now realize most applications contain date and time variables. This beginning tutorial describes how the SAS system 1) stores dates, datetimes, and times; 2) reads date/time variables from "Raw Data Files" and from SAS data sets. It covers when and where to use SAS Informats and formats. Next it describes the easy methods to perform date/time arithmetic via date/time SAS functions.

The paper shows how SAS date Formats can be used in SAS Procedures such as PRINT, FREQ,
and CHART. Finally the tutorial will discuss Year 2000 issues and how SAS software helps you maintain correct date integrity and prevent future Y2k problems in the new millennium.

More can be read at: http://www.kellogg.northwestern.edu/researchcomputing/workshops/papers/finley_sugi25.pdf

How to Read, Write, and Manipulate SAS® Dates:

ABSTRACT:

No matter how long you’ve been programming in SAS, using and manipulating dates still seems to require effort.

Learn all about SAS dates, the different ways they can be presented, and how to make them useful. This paper includes excellent examples in dealing with raw input dates, functions to manage dates, and outputting SAS dates into other formats. Included is all the date information you will need: date and time functions, Informats, formats, and arithmetic operations.

WHAT IS A SAS DATE?
A date is unique within SAS programming. It is neither a character value nor a typical numeric. It is a special case of a numeric variable. In other words, a SAS date is a special representation of a calendar date. Unlike dates in many other languages, SAS has a specific numeric value assigned to each day. The starting point for all SAS dates is January 1st, 1960 and is represented as day zero (0). All previous and subsequent dates are represented with numeric values plus (+) or minus (-) from this starting point. The simplicity of the approach is there will never be a point in the past (since the start of the Gregorian calendar) or future that can not be represented by a
number.

More can be read at: http://analytics.ncsu.edu/sesug/2008/HOW-063.pdf

Working With SAS® System Date and Time Functions

SAS Date, Time, and Datetime Functions

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