[PDF] [PDF] Data Management using Arrays - SAS

[PDF] Using Arrays in SAS Programming - SAS Support

Using Arrays in SAS® Programming Values within the array elements are retained automatically between the iterations of the DATA step – there is no need to use a RETAIN statement Values within the array elements are never written to the output data set

[PDF] 244-2011: The Many Ways to Effectively Utilize Array - SAS Support

At the beginning of the second iteration, since data is read from an existing SAS dataset, the value in the PDV for the ID variable is retained from the previous 

[PDF] 242-30: Arrays Made Easy: An Introduction to Arrays - SAS Support

Once the basics of array processing are understood arrays are a simple solution The values for the temporary data elements are automatically retained across 

[PDF] Data Management using Arrays - SAS

All variables that have been initialized will be retained 9 Page 10 Referencing Array Members To refer an array member 

[PDF] SUGI 24: Transforming SAS(r) Data Sets Using Arrays - SAS Support

ARRAY statement) The values of retained variables are not set to a missing value for each iteration of the Data Step as are the values of non- retained variables

[PDF] SUGI 27: Off and Running with Arrays in SAS(r) - SAS Support

- Initial Values – can be included to give the elements of the array initial values This also causes these variables to be retained during the data step (i e not 

[PDF] Loop-Do-Loop Around Arrays - LexJansen

Arrays are SAS data step statements that allow iterative processing of If the array is initialized, all the variables are retained (even if only some are initialized)

[PDF] RETAIN or NOT? Is LAG Far Behind? - LexJansen

The SAS® documentation has devoted a significant section to the RETAIN statement explaining many finer This is a list of variables NOT comprising an array

[PDF] Effective Use of RETAIN Statement in SAS® Programming

The RETAIN statement allows values to be kept across observations enabling complex data manipulation In SAS variables, or members of an array If a value 

[PDF] Arrays from A to Z - Berkeley Statistics - University of California

SAS arrays can be used for simple repetitive tasks, reshaping data sets, and Array names can be used in RETAIN statements, and, when used with the 

[PDF] sas sum(of array name * )

[PDF] sascrunch arrays

[PDF] sassen cities in a world economy pdf

[PDF] sassen the global city new york london tokyo

[PDF] sat interventions

[PDF] sat practice test 1

[PDF] sat practice test 1 answers

[PDF] sat practice test 10 answers

[PDF] sat practice test 5

[PDF] sat practice test 6 essay

[PDF] sat practice test 6 essay answer

[PDF] sat practice test 6 pdf

[PDF] sat practice test 8

[PDF] sat practice test 9 answers

[PDF] sat practice test pdf

Data Management using SAS Arrays

- Lavanya Vangala 1

9 repetitive actions on a group of variables

9 computing new variables

9 reshaping data

When do we need Arrays?

2

Repetitive action: An Example

We have been given a SAS data set where a value of 999 was entered whenever there was a missing numeric value. General coding Practice (Manual Recoding with If Then): data recode_data; set actual_data; if a =999 then a1=.; if b = 999 then a2=.; if c = 999 then a3=.; if d = 999 then a4=.; if e = 999 then a5=.; if f = 999 then a6=.; Run; 3

What is An Array?

Array is similar to Vector/matrix notation in

Mathematics

Structure:

9Group of variables in a data step

9Elements must be of same data type

9No need of same length

9No need to be related

9Can be multi dimensional

4

ARRAY Statement

ARRAY arrayname {n} [$] [length] array_elements;

ARRAY - is a SAS keyword that specifies that an array is being defined Arrayname - a valid SAS name that is not a variable name in the data set {n} - the index used to give the number of elements in the array ( A numeric constant/Numeric SAS expression /(*) [$] - used to specify if the elements in the array are character variables, the default type is numeric [length] - used to define the length of new variables being created in the array, optional array_elements - a list of variables of the same type (all numeric or all character) to be included in the array 5

SAS DO Loops and Why?

9SAS Array provides a different way to reference a

group of variables

9Reference to the Array elements can be done using

DO loops.

9DO loop should have a corresponding END statement

(Caution !)

9within a single DO loop multiple arrays can be

referenced and operations on different arrays can be performed. 6

Using Arrays ² Recoding variables

For Recoding hundreds of variables arrays are certainly helpful..- Note : Array elements do not need to be named consecutively data recode_data; set actual_data;

Array recode(6) a b c d e f;

Do I = 1 to 6;

If recode(i) = 999 then recode(I) = .;

End;

Drop I;

Run; 7

Extension to All variables

data recode_data; set actual_data;

Array numeric_recodes(*) _numeric_;

Array character_recodes(*) $ _character_;

Do _n_= 1 to dim(numeric_recodes);

If numeric_recodes(_n_) = 999 then numeric_recodes(_n_) = .; End;

Do _n_= 1 to dim(character_recodes);

If character_recodes(_n_) = 'N/A' then character_recodes(_n_) = ''; End; Run; SAS also has a few code words to put all character and/or numeric variables into arrays for you. These can save a lot of typing and is useful for cleaning up missing values in your variables. Note: * - Is used when the number of elements in the array isn't known 8

Assigning Initial values

9Initial values can be assigned to Array members

9Values must always be specified at the end of ARRAY

statement

9Character values need to be in Quotes

Examples:

Array a {10} a1-a10 ( 5 5 5 5 5 5 5 5 5 5 );

Array a{10} (10*5);

Array new {4} $ test1 test4 Sci

quotesdbs_dbs11.pdfusesText_17