What can you do with COMPUTE in SPSS

Note what you can do with Mean.# and Sum.# to tackle missing values. And also take note of LAG which takes up the value of the preceding case.

COMPUTE y=ABS(x). absolute value of x. ABS(!7) =7.
COMPUTE y=SQRT(x). square root
COMPUTE y=LN(x). natural logarithm
COMPUTE y=LG10(x). base 10 logarithm
COMPUTE y=EXP(x). exponential: ex
COMPUTE y=TRUNC(x). integer part. TRUNC(5.7)=5.
COMPUTE y=RND(x). round to nearest integer. RND(5.7)=6
COMPUTE y=MOD(x,11). remainder after division by 11
COMPUTE y=SUM(x1,x2,x3). sum of 3 variables if at least one is non-missing
COMPUTE y=SUM.5(x1 TO x10). sum of 10 variables if at least 5 are non-missing.
COMPUTE y=MEAN.2(x1,x2,x3). mean of 3 variables if at least 2 are non-missing
COMPUTE y=LAG(x). x from previous case
COMPUTE y=$SYSMIS. sets Y to sysmis.

Source: SPSS for Windows 8, 9 and 10 by Svend Juul