Scripting Guide - SAS

Chapter 7 Data Structures 143
Matrices
You can use the Any() or All() operators to summarize matrix comparison results. Any() returns a 1 if
any element is nonzero. All() returns a 1 if all elements are nonzero.
[2 2]==[1 2] // returns [0 1], therefore:
All([2 2]==[1 2]) // returns 0
Any([2 2]==[1 2]) // returns 1
Min() or Max() return the minimum or maximum element from the matrix or matrices given as
arguments.
A=[1 2 3, 4 5 6, 7 8 9, 10 11 12];
B=[0 1 2, 2 1 0, 0 1 1, 2 0 0];
Min(A); // returns 1
Max(A); // returns 12
Min(A,B); // returns 0
Numeric Operations
You can perform numeric operations (such as subtraction, addition, and multiplication) on matrices. Most
statistical methods are expressed in compact matrix notation and can be implemented in JSL.
For example, the following expression uses matrix multiplication and inversion to illustrate least squares
regression:
b
Implement this equation through the following JSL expression:
Basic Arithmetic
= ( X′X) – 1 X′y
b = Inv(X`*X)*X`*y;
You can perform the following basic arithmetic on matrices:
• addition
• subtraction
• multiplication
• division (multiplying by the inverse)
Note: The standard multiply operator is a matrix multiplier, not an elementwise multiplier.
To perform matrix multiplication, use one of the following methods:
• * operator
• Multiply() function
• Matrix Mult() function
To perform matrix division, use one of the following methods:
• / operator