In SPSS, how do I set a variable to the system missing value?

In SPSS, $sysmis is the name of the system missing value. You can include this in a compute statement or in an if statement, as you would any other variable name. For example, if you want to generate the variable temp, which equals the system missing value, the syntax would look like this:

A more common scenario would be to use this variable in a conditional statement. For example, suppose you have two variables (v1 and v2), and you wish to recode all cases of v2 to be equal to the system missing value where v1 is also system missing. Rather than using the recode command, use an if statement like this:

You can use the variable $sysmis only as a value; you cannot use it in the actual conditional statement. If you are searching for cases where v1 is equal to the system missing value, you get this:

When using recode and if statements, set up a condition using the missing value by specifying sysmis(variable). Do not use the regular  =  (equals) sign.

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