Scripting Guide - SAS

142 Data Structures Chapter 7
Matrices
P[1,1]+=1;
Show(P);
P=[3 2 3,
4 5 6,
7 8 9];
Ranges of Rows or Columns
If you are working with a range of subscripts, use the Index() function :: to create matrices of ranges.
T1=1::3; // creates the vector [1 2 3]
T2=4::6; // creates the vector [4 5 6]
T3=7::9; // creates the vector [7 8 9]
T=T1|/T2|/T3; // concatenates the vectors into a single matrix
T[1::3, 2::3]; // refers to rows 1 through 3, columns 2 and 3
[2 3, 5 6, 8 9]
T[index(1,3), index(2,3)]; // equivalent Index function
[2 3, 5 6, 8 9]
Inquiry Functions
The NCol() and NRow() functions return the number of columns and rows in a matrix (or data table),
respectively:
NCol([1 2 3,4 5 6]); // returns 3 (for 3 columns)
NRow([1 2 3,4 5 6]); // returns 2 (for 2 rows)
To determine whether a value is a matrix, use the Is Matrix() function, which returns a 1 if the argument
evaluates to a matrix.
A = [20, 64, 3];
B = {20, 64, 3};
IsMatrix(A); // returns 1 for yes
IsMatrix(B); // returns 0 for no
Comparisons, Range Checks, and Logical Operators
JMP’s comparison, range check, and logical operators work with matrices and produce matrices of
elementwise Boolean results. You can compare conformable matrices.
A=B; // greater or equal
A==B; // equal to
A!=B; // not equal to
A