SPSS® 12.0 Command Syntax Reference

938 MATRIX—END MATRIX
• The first PRINT subcommand uses the default format with as the multiplier for each
element of the matrix. This results in the following output:
Default format
10 ** 9 X
.000000000 .000000002 3.690000000
Note that the first element is displayed as 0 and the second is rounded to one significant
digit.
• An explicitly specified exponential format on the second PRINT subcommand allows each
element to be displayed with full precision, as the following output shows:
Explicit exponential format
1.3570000E-10 2.4680000E+00 3.6900000E+09
Matrix Control Structures
The matrix language includes two structures that allow you to alter the flow of control within
a matrix program.
• The DO IF statement tests a logical expression to determine whether one or more subsequent
matrix statements should be executed.
• The LOOP statement defines the beginning of a block of matrix statements that should
be executed repeatedly until a termination criterion is satisfied or a BREAK statement is
executed.
These statements closely resemble the DO IF and LOOP commands in the SPSS transformation
language. In particular, these structures can be nested within one another as deeply as
the available memory allows.
DO IF Structures
A DO IF structure in a matrix program affects the flow of control exactly as the analogous
commands affect an SPSS transformation program, except that missing-value considerations
do not arise in a matrix program. The syntax of the DO IF structure is as follows:
DO IF [(]logical expression[)]
matrix statements
[ELSE IF [(]logical expression[)]]
matrix statements
[ELSE IF...]
.
.
.
[ELSE]
matrix statements
END IF.
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