SPSS® 12.0 Command Syntax Reference

918 MATRIX—END MATRIX
Example
{11;12;13}
• This example represents a column vector:
Example
{3}
11
12
13
• This example represents a scalar. The braces are optional. You can specify the same scalar
as 3.
Matrix Notation Shorthand
You can simplify the construction of matrices using notation shorthand.
Consecutive Integers. Use a colon to indicate a range of consecutive integers. For example,
the vector {1,2,3,4,5,6} can be written as {1:6}.
Incremented Ranges of Integers. Use a second colon followed by an integer to indicate the increment.
The matrix {1,3,5,7;2,5,8,11} can be written as {1:7:2;2:11:3},
where 1:7:2 indicates the integers from 1 to 7 incrementing by 2, and 2:11:3 indicates
the integers from 2 to 11 incrementing by 3.
• You must use integers when specifying a range in either of these ways. Numbers with fractional
parts are truncated to integers.
• If an arithmetic expression is used, it should be enclosed in parentheses.
Extraction of an Element, a Vector, or a Submatrix
You can use indexes in parentheses to extract an element from a vector or matrix, a vector
from a matrix, or a submatrix from a matrix. In the following discussion, an integer index
refers to an integer expression used as an index, which can be a scalar matrix with an integer
value or an integer element extracted from a vector or matrix. Similarly, a vector index
refers to a vector expression used as an index, which can be a vector matrix or a vector
extracted from a matrix.