2. • Use the paste button on any
dialog box
• Record commands in the log
Edit –> Options –> Viewer
• Retrieve commands from the
journal file - statistics.jnl.
Edit –> Options –> File Locations
• Auto-complete in the syntax
editor and build commands
interactively
How to create a syntax file
2
3. • Highlight the commands you
want to run in a command syntax
window
• Invoke one command file from
another using the INCLUDE or
INSERT command
• Use the production facility to run
syntax files
• Use the Statistics Batch Facility
(Statistics Server)
Running commands in a syntax file
3
•Utilities -> Production Facility
4. It is often necessary to recode or modify original variables
Best practise is to assign the modified values to new
variables and keep the original variables unchanged
Creating a new variable allows you to compare the initial and
the modified values to verify the recode/modification has
been done correctly
Do not Overwrite Original Variables
4
5. Instead of overwriting the variable always create a new one
• COMPUTE var1=var1*2
• COMPUTE var1_new=var1*2
• RECODE var2 (1 thru5=1)(6 thru 10 = 2)
• RECODE var2 (1 thru5=1)(6 thru 10 = 2)(ELSE=COPY) /INTO var2_new
Overwriting Variables in Syntax
5
6. For transformations that require intermediate variables
temporary (or scratch) variables can be used
Any variable name that begins with a # is treated as a
temporary variable
These variables are discarded at the end of a series of
transformations when SPSS encounters an EXECUTE
command or other commands that read the data
Using Temporary Variables
6
7. This example syntax creates a variable called var1 and then
computes the factorial (n!)
DATA LIST FREE / var1.
BEGIN DATA
1 2 3 4 5
END DATA.
COMPUTE factor=1.
LOOP #tempvar=1 TO var1.
-COMPUTE factor=factor * #tempvar.
END LOOP.
EXECUTE.
A temporary variable tempvar is used to do the calculation: n*(n-
1)*(n-2)*(n-3) * ...*1
This is done within a LOOP – END LOOP structure
Example using Temporary variables
7
8. SPSS is designed to minimise the number of times it has to
read the data, however each time an EXECUTE command is
executed through syntax the data is read.
Statistical and Charting procedures always read the data but
most transformation commands do not require a separate
data pass
Creating command syntax from pasting different procedures
can include a lot of extra EXECUTE commands which can
increase processing time
Use EXECUTE sparingly
8
9. In most cases virtually all of the auto-generated EXECUTE
commands can be removed, and this will speed up
processing
To turn off the automatic, immediate execution of
transformations and the associated pasting of EXECUTE
commands:
Edit -> Options -> Data tab: Calculate values before used.
Use EXECUTE sparingly
9
10. Instead of working with very large syntax files with 1000’s of
lines of code, break down your syntax file into a number of
standalone files
You might have a syntax separate file for:
• Preparing and standardising data
• Merging data files
• Performing tests on data
• Running reports
Using the INSERT command and a master command file
that specifies all of the other command files you can partition
all your tasks into separate command files
Using the INSERT command
10
11. The INSERT command provides a method for linking
multiple syntax files together making it possible to reuse
blocks of command syntax
Using the INSERT command
11
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