/* Writing Valid Syntax */

* Commands begin with a keyword, end with a period "." (on most operating systems), and usually
*    include a mix of key words and user-chosen variable names.

*e.g
COMMAND 
  /subcommand keyword=option
  / subcommand variables.
get file = "Y:\spss\data\cars.sav".

get file = "Y:\spss\data\cars.sav"
  /keep=mpg weight.

* See DESCRIPTIVES example in the Syntax Reference Guide.

descriptives variables=mpg.

descriptives variables=mpg
  /statistics.
descriptives variables=mpg
  /statistics=default.

get file = "Y:\spss\data\cars.sav".
descriptives variables=all.
descriptives variables=all 
  /sort.

/* Capitalization does not matter */
GET FILE='Y:\SPSS\Data\1991 U.S. General Social Survey.sav'.

get file = "Y:\spss\data\cars.sav".

/* Under Windows, commands may start in any column, and end with a period at the end of a line. */

     GET FILE='Y:\SPSS\Data\1991 U.S. General Social Survey.sav'.

* However, with other operating systems, commands must begin in column one, so it is a
	good habit to always start your commands in column one.

/*  Commands may be continued on more than one line.  Any continuation _should_ leave column one empty. */

/* This works well: */
FREQUENCIES
  VARIABLES=sex.

/* Under Windows, this also works, but under other operating systems it doesn't: */
FREQUENCIES
VARIABLES=sex.

/* Blank lines in the middle of commands never work: */
FREQUENCIES

VARIABLES=sex.

/* But blank lines between commands are fine. */

get file = "y:\spss\data\cars.sav".

frequencies variables=year .

* You may use spaces or not between tokens.
compute kilos=weight/2.20462.
compute kpl  = mpg /  (0.621371 * 3.78541)  .
execute.
* It is possible to abbreviate most SPSS keywords, although this is not common 
    practice.  So you may occasionally see code that looks like this:  .

fre var=year .

* Comments:  three ways to specify comments.
* pounds/(pounds/kilogram).
compute kilos=weight/2.20462.
comment "kpl" is kilometers per liter.  This is
  calulated as (miles/gallon) / ((miles/kilometers) * (liters/gallon)).
compute kpl  = mpg /  (0.621371 * 3.78541)  .
execute.

* Note:  Correlation is unchanged by change of scale.
correlations variables= kilos kpl  /*weight mpg..
graph /scatterplot = kilos with kpl.
correlations variables= /*kilos kpl*/ weight mpg.
graph /scatterplot = weight with mpg.