introduction to sas statistical package · 1 introduction to sas statistical package biostatistics...

1

Introduction to SASStatistical Package

Biostatistics 140.632Lecture 1

2

Instructor:Lucy Meoni [email protected] Assistant :Sorina Eftim [email protected]/Lab: Room 3017WEB site:

www.biostat.jhsph.edu/bstcourse/bio632/default.htm

e-mail: [email protected] to submit exercises

3

Using the PC labsSAS Version 9.0

• requires basic Windows skills• Set up class folder on your media

(thumb drive, diskette)• download files from the website for lab

into class folder• bring thumb drive or diskette to class

4

Text : ‘The Little SAS Book 3rd edition’

Other References:

SAS online documentation

Online tutor

SAS system help

Many, many SAS manuals

SAS website www.sas.com

5

WHAT IS SAS?

Integrated system of software products

• began as software package for statistical analysis

• data management

• reporting and graphics

• analytic

• etc.6

COURSE OBJECTIVES

• to introduce and develop skills in SAS; a statistical package used in research data analysis

• develop the skills necessary to create and modify a SAS data set and perform statistical analyses

2

7

COURSE TOPIC SEQUENCE• introduction to SAS

• data definition and restructuring

• dates and functions

• file combination

• arrays and loops

• statistical procedures

8

REFERENCE

The Little SAS Book Chapter 1 and 2

WEB site:

www.biostat.jhsph.edu/bstcourse/bio632/default.htm

9

TOPICS:• Introduction to SAS

• SAS programs• SAS windowing environment• SAS tables (data sets)• SAS libraries• Creating SAS tables − IMPORT wizard− StatTransfer

• Temporary vs permanent files10

SAS• use statements to write a series of

instructions called a SAS program• not command line driven (STATA)• statements are written using the SAS

language (a programming language that you use to manage your data).

• sequence of statements executed in order

• SAS procedures are software tools for data analysis and reporting.

11

The SASProgramming

ProcessCreate a SAS Program

Enter the SAS Program Code

Process the SAS Program Code

Review the Results

Debug or Modify

Define the Need

Introduction to SAS Programs

3

13

DATA steps are typically used to create SAS data sets.

PROC steps are typically used to process SAS data sets (that is, generate reports and graphs, edit data, and sort data).

A SAS program is a sequence of steps that the user submits for execution.

RawData

DATAStep

Report

SASData Set

SASData Set

PROCStep

SAS Programs

14

LIBNAME mylib 'd:\temp\sasclass';DATA newclass; SET mylib.class;BMI=(weight*.454)/((height*.0254)**2);

PROC PRINT DATA=newclass;

PROC MEANS DATA=newclass;CLASS gender;VAR bmi;RUN;

DATA Step

PROC Steps

SAS Program

15

SAS steps begin with a

DATA statement

PROC statement.

SAS detects the end of a step when it encounters

a RUN statement (for most steps)

a QUIT statement (for some procedures)

the beginning of another step (DATA statement or PROC statement).

Step Boundaries

16

DATA newclass; SET mylib.class;BMI=(weight*.454)/((height*.0254)**2);


PROC MEANS DATA=newclass;CLASS gender;VAR bmi;

RUN;

Step Boundaries : Lecture1.sas

Running SAS Programs

18

– Invoke the SAS System and include a SAS program into your session.

– Submit a program and browse the results.

– Navigate the SAS windowing environment.

Objectives

4

19

Interactive windows enable you to interface with SAS.SAS Windowing Environment

Navigating the SAS Windowing Environment

21

Define the Need

Create a SAS Program



Review the Results

Debug or Modify

The SAS Programming

Process

22

Define the Need

Create a SAS Program



Review the Results

Debug or Modify

The SASProgramming

Process

Entering and Executing SAS Code

24

Objectives

• Enter SAS program code in the SAS windowing environment and execute the program.

5

25


Once the planning and coding effort for a SAS program is complete, the SAS program code must be entered into the computer to process and to test the program.

26

Windowing Mode

Windowing mode is a facility that enables you to enter and execute SAS programs and view the results in an interactive environment.An interactive environment permits the program to be processed immediately when submitted for execution.

27

The SAS windowing environment is made up of a collection of windows.

There are three primary windows in the windowing environment.

3 2 1

28

The Enhanced Program Editor window enables SAS program code to be

• entered from the keyboard

• submitted for execution.

• SAS program elements are color-coded, including procedures, keywords, numeric and string constants, undefined keywords.

29

The Log window displays

• the SAS program code submitted for execution

• messages from SAS indicating the status of the program execution.

30

The Output window

• displays reports generated by the SAS program.

6

31

Commands are used to navigate among the various windows of the SAS windowing environment and are used to execute a program.

Depending upon the operating environment, commands can be issued by ...

32

Selecting from pull-down menu

Typing the command

Using function keys (F1 - F12)

Clicking on a tool button

33

Entering and Executing SAS Code

This demonstration illustrates entering SAS program code into the SAS Windowing Environment and executing the program.

34

SAS Windowing Environment

• windowing system for editing and executing SAS programs

• interactive full screen

• collection of windows for editing programs, executing programs and displaying results

• five basic SAS windows

35

Starting SAS

• Start SAS from the START button, PROGRAMS, The SAS System for Windows V9 system

• interactive full screen

• Enhanced Editor window, LOG window, and Explorer windows appear

• activate window by clicking within the window

36

7

37

ENHANCED PROGRAM EDITOR• text editor

• write and edit programs

• submit programs (use SUBMIT icon)

• save program statements to file with extension .sas

• asterisk (*) appears in title bar to indicate file has not been saved

• multiple windows possible38

ENHANCED PROGRAM EDITOR

• an ASCII editor that uses visual aides to help you write and debug your SAS programs.

• SAS program elements are color- coded, including procedures, keywords, informats and formats, dates, numeric and string constants, macro keywords, undefined keywords, and more.

• File, Open on menu to read in an existing SAS program file

39 40

LOG Window

• contains the compilation and execution results of DATA

• contains submitted program statements• messages from SAS about compilation

and execution -notes, warnings, errors• save contents of this window to a file

with extension .log (File, Save menu)• clear window by clicking NEW icon on

Toolbar

41

LOG WINDOW CONTENTS• DATA Step

• name of the SAS data set read and the number of observations and variables in the data set

• name of the SAS data set created and the number of observations and variables in the new SAS data set

42

LOG WINDOW

PROC Steps

• index with page numbers for “successful” procedures

8

43 44

OUTPUT WINDOW

• printable results from procedures

• save contents of this window to a

• file with extension .lst

• empty if program did not run

• - CHECK LOG window for errors

• indexed in the RESULTS window

• clear window and by clicking on NEW icon on Toolbar

45 46

47

RESULTS WINDOW• table of contents for OUTPUT

window

• lists each part of your results in an outline form

• possible to save and/or print sections of results by right-clickingon section

48

9

49

EXPLORER WINDOW

• provides access to SAS files and libraries

• similar to Windows Explorer

50

51

SAS FILE ORGANIZATION

File Type Extensionprogram file (EDITOR window) .sasSAS table (data set) .sas7bdatlog file (LOG window) .logListing file (OUTPUT) .lst

52

When you execute a SAS program, the output generated by SAS is divided into two major parts:

SAS log contains information about the processing of the SAS program, including any warning and error messages.

SAS output contains reports generated by SAS procedures and DATA steps.

Submitting a SAS Program

53

Running a SAS Program

lecture1.sas

• This demonstration illustrates how to start a SAS session, include and submit a SAS program, and browse the results.

54

SAS Log1 LIBNAME mylib 'd:\temp\sasclass';NOTE: Libref MYLIB was successfully assigned as follows:

Engine: V9Physical Name: d:\temp\sasclass

2 DATA newclass; SET mylib.class;3 BMI=(weight*.454)/((height*.0254)**2);4NOTE: There were 5 observations read from the data set MYLIB.CLASS.NOTE: The data set WORK.NEWCLASS has 5 observations and 7 variables.5 PROC PRINT DATA=newclass;6NOTE: There were 5 observations read from the data set WORK.NEWCLASS.7 proc means DATA=newclass;8 var bmi ;9 class gender;10 run;NOTE: There were 5 observations read from the data set WORK.NEWCLASS.1112 RUN;

10

55

PROC PRINT Output

lname baseage gender race weight height BMI

1 Richardson 34 1 2 189 72 25.65582 Lowrey 29 2 1 235 71 32.80503 Tierney 32 1 2 229 70 32.88734 Sommers 33 2 1 156 66 25.20145 Kegan 19 2 1 140 65 23.3179

56

The SAS System The MEANS Procedure

Analysis Variable : BMIN

gender Obs N Mean Std Dev ƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒ

1 2 2 29.2715252 5.1134352 2 3 3 27.1081032 5.0227067

ƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒMinimum Maximum

ƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒ25.6557805 32.887269923.3179165 32.8049654

ƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒ

PROC MEANS Output

57

Exercise I ONLYMastering Fundamental Concepts

59

– Define the components of a SAS data set.– Define a SAS variable.– Identify a missing value and a SAS date

value.– State the naming conventions for SAS data

sets and variables.– Explain SAS syntax rules.– Investigate a SAS data set using the

CONTENTS and PRINT procedures.

Objectives

60

SAS Data Sets

Data Entry

External File

Conversion Process

SAS Data Set

Descriptor Portion

Data Portion

Other Software

Files

11

61

General data set information * data set name * data set label* date/time created * storage information* number of observations

Information for each variable* Name * Type * Length * Position* Format * Informat * Label

Descriptor Portion

Data Portion

SAS data sets have a descriptor portion and a data portion.

SAS Data Sets

62

• descriptor portion of a SAS data set contains– general information about the SAS data set (such

as data set name and number of observations)– variable attributes (name, type, length, position,

informat, format, label).

• CONTENTS procedure displays the descriptor portion of a SAS data set.

Browsing the Descriptor Portion

63

• General form of the CONTENTS procedure:

•

• Example:

PROC CONTENTS DATA=SAS-data-set;RUN;

proc contents data=work.newclass;run;

Browsing the Descriptor Portion

64

The CONTENTS Procedure

Data Set Name WORK.NEWCLASS Observations 5Member Type DATA Variables 7Engine V9 Indexes 0Created Friday, March 18, 2005 04:02:40 PM Observation Length 64Last Modified Friday, March 18, 2005 04:02:40 PM Deleted Observations 0Protection Compressed NOData Set Type Sorted NOLabel

Alphabetic List of Variables and Attributes

# Variable Type Len Format Informat

7 BMI Num 82 baseage Num 8 BEST12. F12.3 gender Num 8 BEST12. F12.6 height Num 8 BEST12. F12.1 lname Char 15 $F15. $F15.4 race Num 8 BEST12. F12.5 weight Num 8 BEST12. F12.

Partial PROC CONTENTS OUTPUT

65

Numeric values

Varia

ble

nam

esVaria

ble

values

lname gender BMI

Richardson 1 25.6558Lowrey 2 32.8050Tierney 1 32.8873Sommers 2 25.2014Kegan 2 23.3179

The data portion of a SAS data set is a rectangular table of character and/or numeric data values.

Character values

SAS Data Sets: Data Portion

66

SAS Variable ValuesThere are two types of variables:Character contain any value: letters, numbers,

special characters, and blanks. Character values are stored with a length of 1 to 32,767bytes. One byte equals one character.

Numeric stored as floating point numbers in 8bytes of storage by default. Eight bytes of floating point storage provide space for 16 or 17 significant digits. You are not restricted to 8 digits.

12

67

SAS names • can be 32 characters long.• can be uppercase, lowercase, or mixed-

case.• must start with a letter or underscore.

Subsequent characters can be letters, underscores, or numeric digits.

SAS Data Set and Variable Names

68

• Select the valid default SAS names.

data5mon

5monthsdata

five months data

fivemonthsdata

data#5

Valid SAS Names

five_month_data

69

• Select the valid default SAS names.

data5mon

5monthsdata

five months data

fivemonthsdata

data#5

Valid SAS Names

five_month_data

70

• SAS stores date values as numeric values.• A SAS date value is stored as the number of

days between January 1, 1960, and a specific date.01JAN1959 01JAN1960 01JAN1961

store-365 0 366

display

01/01/1959 01/01/1960 01/01/1961

SAS Date Values

71

LastName FirstName JobTitle Salary

TORRES JAN Pilot 50000LANGKAMM SARAH Mechanic 80000SMITH MICHAEL Mechanic . WAGSCHAL NADJA Pilot 77500TOERMOEN JOCHEN 65000

A value must exist for every variable for each observation. Missing values are valid values.

A numeric missing value is displayed as a period.

A character missing value is displayed as a blank.

Missing Data Values

72

•The PRINT procedure displays the data portion of a SAS data set.

•By default, PROC PRINT displays– all observations– all variables– an Obs column on the left side.

Browsing the Data Portion

13

73

• General form of the PRINT procedure:•

• Example:

PROC PRINT DATA=SAS-data-set;RUN;

proc print data=work.newclass;run;

c02s3d1

Browsing the Data Portion

74

The SAS System

Obs lname baseage gender race weight height BMI

1 Richardson 34 1 2 189 72 25.65582 Lowrey 29 2 1 235 71 32.80503 Tierney 32 1 2 229 70 32.88734 Sommers 33 2 1 156 66 25.20145 Kegan 19 2 1 140 65 23.3179

PROC PRINT Output

75

SAS documentation and text in the SAS windowing environment use the following terms interchangeably:

SAS Data Set SAS Table

Variable Column

Observation Row

SAS Data Set Terminology

76

SAS statementsusually begin with an identifying keywordalways end with a semicolon.




RUN;

SAS Syntax Rules

77

SAS statementsusually begin with an identifying keywordalways end with a semicolon.

DATA newclass; SET mylib.class;BMI=(weight*.454)/((height*.0254)**2);RUN;

PROC PRINT DATA=newclass;RUN;

PROC MEANS DATA=newclass;CLASS gender;VAR bmi;RUN;

SAS Syntax Rules

78

SAS statements are free-format.One or more blanks or special characters can be used to separate words.They can begin and end in any column.A single statement can span multiple lines.Several statements can be on the same line.

Unconventional Spacing

...


PROC PRINT DATA=newclass;PROC MEANS DATA=newclass;CLASS gender; VAR bmi; RUN;

SAS Syntax Rules

14

79

Good spacing makes the program easier to read.

Conventional Spacing




RUN;

SAS Syntax Rules

80

Type * to begin a comment.Type your comment text.Type ; to end the comment.

* Create work.staff data set and add bmi;DATA newclass; SET mylib.class;

BMI=(weight*.454)/((height*.0254)**2);

* Produce listing report of newclass ;PROC PRINT DATA=newclass;RUN;

SAS Comments

Getting Familiar with SAS® Data Sets

SAS Data Libraries

83

Objectives

– Explain the concept of a SAS data library.– State the difference between a permanent

library and a temporary library.– Use the CONTENTS procedure to

investigate a SAS data library.

84

A SAS data library is a collection of SAS files that are recognized as a unit by SAS.

Windows: c:\mysasfilesUNIX: /users/dept/mysasfiles

SAS Data Library

SAS File

SAS File

SAS File

A SAS data set is a type of SAS file.

Directory-based A SAS data library isSystems a directory.

SAS Data Libraries

15

85

FILES

LIBRARIES

You can think of a SAS data library as a drawer in a filing cabinet and a SAS data set as one of the file folders in the drawer.

SAS Data Libraries

86

Regardless of which host operating system you use, you identify SAS data libraries by assigning each a library reference name (libref).

libref

Assigning a Libref

87

work

sasuser

ia

work - temporary library

sasuser - permanent library

When you invoke SAS, you automatically have access to a temporary and a permanent SAS data library.

You can create and access your own permanent libraries.

ia - permanent library

SAS Data Libraries

88

LIBNAME libref 'SAS-data-library' <options>;

Rules for naming a libref: must be 8 characters or lessmust begin with a letter or underscoreremaining characters are letters, numbers, or underscores.

Assigning a Libref• You can use the LIBNAME statement to assign a

libref to a SAS data library.• General form of the LIBNAME statement:

89

libname ia 'c:\workshop\winsas\prog1';

Assigning a Libref• Examples:

libname sasclass ‘d:\temp\sasclass';

Libref exists only during the current SAS session

90

• When you submit the LIBNAME statement, a connection is made between a libref in SAS and the physical location of files on your operating system.

Windows 'c:\workshop\winsas\prog1'

Making the Connection

16

91

The first name (libref) refers to the library.

Every SAS file has a two-level name:

The second name (filename) refers to the file in the library.

The data set ia.sales is a SAS file in the ia library.libref.filename

sasuser

work

ia

sales

Two-level SAS Filenames

92

work.employee employee

Temporary SAS Filename

• The libref work can be omitted when you refer to a file in the work library. The default libref is work if the libref is omitted.

files are deleted when SAS session ends

93 94

95 96

SAS Files

SAS data sets and other files are stored in SAS data libraries.

SASUSER

WORK

MYLIB

17

97

SAS Data Libraries•A SAS data library is a collection of SAS files that are recognized as a unit by SAS on your operating environment.

WORK - temporary library

SASUSER - permanent library

You can create and access your own permanent libraries.

mylib - permanent library

WORK

SASUSER

MYLIB

98

The LIBNAME Statement

• LIBNAME statement establishes the library reference (or libref), which is an alias for the SAS data library.

• global statement - in effect for the entire SAS session until replaced

• General form of the LIBNAME statement:

LIBNAME libref 'SAS-data-library' <options>; Ex: LIBNAME mylib ‘your folder’;

The libref must be eight characters or fewer.

99

Two-Level SAS Data Set Names

LibrefSAS Data

Library

SAS Data

libref.SAS-filename

100

SAS DATA SET NAMES• 2 level names • first level is the libref

refers to location of the fileDefault - file stored in WORK library

• second level is the member name that identifies the data set within the library

Example :

work.sales-located in the WORK library

mylib.sales-located in the MYLIB library

101

DATA Step

PROC Step

DATA Step

PROC Step

PROC Step

SAS Program may consist of a DATA Step

Or a PROC Step

Or any combination of DATA and PROC Steps

102

EXERCISES II-IV

18

103

DATA Step -- Two Phase Process

Phase 1 - Compile phasecorresponds to descriptor portion

Phase 2 - Execute phasecorresponds to data portion

104

CompilationDuring compilation, SASchecks code for syntax errorstranslates code to machine codeestablishes an area of memory called the

input buffer if reading raw dataestablishes an area of memory called the

Program Data Vector (PDV)assigns required attributes to variablescreates the descriptor portion of the new data

set.

105

ExecutionDuring the execution phase, SASinitializes the PDV to missingreads data values into the PDVcarries out assignment statements and

conditional processing writes the observation in the PDV to the output

SAS data set at the end of the DATA step (by default)

returns to the top of the DATA stepinitializes any variables that are not read from a

SAS data set to missing (by default)repeats the process. 106

StopDATAstep.

YES

Initialize PDV.

Execute “read” statement.

End of file?

NOExecute program statements.

Output observation to SAS data set.

The DATA Step Is a Loop

Reading SAS Data Sets and Creating Variables

108

Objectives

Create a SAS data set using another SAS data set as input.

Create SAS variables.

Use operators and SAS functions to manipulate data values.

Control which variables are included in a SAS data set.

19

109

Create a temporary SAS data set named newclass2 from the permanent SAS data named mylib.class2 and create a variable that represents the bmi.

Compute BMI from the variable Height and Weight.

New Variable

Reading a SAS Data Set

Lname Birthdate Baseage Weight Height Richardson 2225 34 189 72

Lowrey 3734 29 235 71

Tierney . 32 229 70

Sommers -205 33 156 66

BMI

25.6558

32.8050

32.8873

25.2014

SAS date valuesmylib.class2

110

• To create a SAS data set using a SAS data set as input, you must use aDATA statement to start a DATA step and

name the SAS data set being created (output data set: newclass2)

SET statement to identify the SAS data set being read (input data set: myib.class2).


To create a variable, you must use anassignment statement to uses the values of the variables Weight and Height and assign the result of the calculation to the variable BMI.

111

• By default, the SET statement reads all of the observations from the input SAS data set variables from the input SAS data set.

General form of a DATA step:


DATA output-SAS-data-set;SET input-SAS-data-set;additional SAS statements

RUN;

112

• An assignment statementevaluates an expressionassigns the resulting value to a variable.

General form of an assignment statement:

Assignment Statements

variable=expression;

113

Define the Variable

valuevalue

expressionnew_variable_name =

EVALUATE

ASSIGN

114

Name the New Variable

Rules for naming SAS variables:• 1 to 32 characters in length• start with a letter (A through Z) or an

underscore (_)• continue with any combination of

numbers, letters, or underscores• can be stored in mixed-case.

20

115

Operators are symbols that request arithmetic calculationsSAS functions.

Operands arevariable namesconstants.

An expression contains operands and operators that form a set of instructions that produce a value.

SAS Expressions

116

EXAMPLES

• x=3; assigns 3 to X for all observations

• y=age/10; assigns the value of age divided by 10 to each observation

• Clinic=’Boston’; assigns the character constant Boston to the variable clinic for each observation

• bmi= wgtkg/(htm**2); assigns results of calculationto new variable bmi

NOTE : X Y and bmi are numeric variables; clinic is a character variable

117

Selected operators for basic arithmetic calculations in an assignment statement:

Operator Action Example Priority

+ Addition Sum=x+y; III

- Subtraction Diff=x-y; III

* Multiplication Mult=x*y; II

/ Division Divide=x/y; II

** Exponentiation Raise=x**y; I

- Negative prefix Negative=-x; I

Using Operators

118

Lname $ 15

BaseageN 8

Bdate N 8

Race N 8

Weight N 8

HeightN 8

PDV

Compiling the DATA Step

libname mylib 'SAS-data-library';data newclass2;

set mylib.class2;BMI=(weight*.454)/((height*.0254)**2);run;

...

119

lname $ 15

baseage N 8

Gender N 8

Race N 8

Weight N 8

HeightN 8

BMI N 8

PDV

Compiling the DATA Step

libname mylib 'SAS-data-library';data newclass2;

set mylib.class2;BMI=(weight*.454)/((height*.0254)**2);

run;

...120

Lname Birthdate Baseage Weight Height Bmi . . . . .

Mylib.class2

PDV

newclass2

Executing the DATA Step

data newclass2;set mylib.class2;

BMI=(weight*.454)/((height*.0254)**2);run;

Lname Birthdate Baseage Weight Height Bmi

...

Lname Birthdate Baseage Weight HeightRichardson 2225 34 189 72 Lowrey 3734 29 235 71 Tierney . 32 229 70

21

121

Lname Birthdate Baseage Weight Height Bmi Richardson 2225 34 189 72 .

Mylib.class2

PDV

newclass2





...


122

Lname Birthdate Baseage Weight Height Bmi Richardson 2225 34 189 72 25.6558

Mylib.class2

PDV

newclass2





...


123






Automatic return

...

PDV

newclass2

Mylib.class2Lname Birthdate Baseage Weight HeightRichardson 2225 34 189 72 Lowrey 3734 29 235 71 Tierney . 32 229 70

Automatic output

124





Reinitialize Totalto missing

...

PDV

newclass2

Mylib.class2

Lname Birthdate Baseage Weight Height Bmi Richardson 2225 34 189 72 .


125




...

PDV

newclass2


Lname Birthdate Baseage Weight Height Bmi Lowery 3724 29 235 71 .


126




...

PDV

newclass2


Lname Birthdate Baseage Weight Height Bmi Lowery 3724 29 235 71 32.8050


22

127




...

PDV

newclass2

Mylib.class2Lname Birthdate Baseage Weight HeightRichardso 2225 34 189 72 Lowrey 3734 29 235 71 Tierney . 32 229 70

Lname Birthdate Baseage Weight Height Bmi Lowery 3724 29 235 71 32.8050


Lowery 3724 29 235 71 32.8050

Automatic return

Automatic output

128Why is BMI missing in observation 5?

Assignment Statementsproc print data=newclass2;

format birthdate date9.;var lname birthdate height weight bmi;

run;

Obs lname birthdate height weight BMI

1 Richardson 03FEB1966 72 189 25.65582 Lowrey 23MAR1970 71 235 32.80503 Tierney . 70 229 32.88734 Sommers 10JUN1959 66 156 25.20145 Kegan 08AUG1980 . 140 .

129

Printing DatesPROC PRINT data=example;Var id birthdate;Format mmddyy10.; SPECIFY FORMATRun;Obs id birthdate

1 14632 03/04/1993 2 67456 05/28/1991

Without format1 14632 12116 2 67456 11470

130

SAMPLE SAS DATA FORMATS

Print: SAS format:

040197 MMDDYY6.04/01/97 MMDDYY8.04/01/1997 MMDDYY10.010497 DDMMYY6.01/04/97 DDMMYY8. 01/04/1997 DDMMYY10. 01APR97 DATE7.01APR1997 DATE9.

Portions © Copyright 2001 SAS Institute Inc., Cary, NC, USA. All Rights Reserved. Reproduced with

permission from SAS Institute Inc., Cary NC, USA.

introduction to sas statistical package · 1 introduction to sas statistical package biostatistics...

Documents