|Introduction to SAS/IML Software
SAS/IML Software: An Overview
You can program easily and efficiently with the many features
for arithmetic and character expressions in SAS/IML software.
You have access to a wide range of built-in subroutines
designed to make your programming fast, easy, and efficient.
Because SAS/IML software is part of the SAS System, you can
access SAS data sets or external files with an extensive
set of data processing commands for data input and output,
and you can edit existing SAS data sets or create new ones.
SAS/IML software has a complete set of control statements,
such as DO/END, START/FINISH,
iterative DO, IF-THEN/ELSE,
GOTO, LINK, PAUSE,
and STOP, giving you all of the commands
necessary for execution control and program modularization.
While most programming languages deal with single data
elements, the fundamental data element with SAS/IML
software is the matrix, a two-dimensional (row ×
column) array of numeric or character values.
You can access built-in matrix operations that require
calls to math-library subroutines in other languages.
You have access to many operators,
functions, and CALL subroutines.
You can add elements of the matrices A and
B with the expression A+B.
You can perform matrix multiplication with the expression
A*B and perform elementwise
multiplication with the expression A#B.
You can execute a command as soon as you enter it, or
you can collect commands in a module to execute later.
When you execute a command, you see the results immediately.
You can interact with an executing module by
programming IML to pause, enabling you to enter
additional statements before continuing execution.
You do not need to declare, dimension, and allocate storage
for a data matrix. SAS/IML software does this automatically.
You can change the dimension or type of a matrix at any time.
You can open multiple files or access many libraries.
You can reset options or replace modules at any time.
You can read all observations or read conditionally selected
observations from a SAS data set into a matrix, creating either
multiple vectors (one for each variable in the data set) or
a matrix that contains a column for each data set variable.
You can create a new SAS data set, or you can edit
or append observations to an existing SAS data set.
You have access to a wide range of graphics commands,
enabling you to visually explore relationships in data.
Copyright © 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.