SPSS® 12.0 Command Syntax Reference

258 COMPUTE
• V2 is a pseudo-random number from a distribution with a mean of 0 and a standard deviation
of the specified value of 1.5.
• You can change the seed value of the pseudo-random-number generator with the SEED
specification on SET.
Date and Time Aggregation Functions
COMPUTE OCTDAY=DATE.YRDAY(1688,301).
COMPUTE QUART=DATE.QYR(QTR,YEAR).
COMPUTE WEEK=DATE.WKYR(WK,YEAR).
• OCTDAY is the 301st day of the year 1688. With a DATE format, OCTDAY displays as
27-OCT-1688.
• QUART reads values for the quarter from the variable QTR and values for the year from
the variable YEAR. If QTR is 3 and YEAR is 88, QUART with a QDATE format displays as
3 Q 88.
• WEEK takes the value for the week from the variable WK and the value for the year from
the variable YEAR. If WK is 48 and YEAR is 57, WEEK with a DATE format displays as
26-NOV-57.
Date and Time Conversion Functions
COMPUTE NMINS=CTIME.MINUTES(TIME.HMS(HR,MIN,SEC)).
COMPUTE AGER=(YRMODA(1992,10,01)-
YRMODA(YRBIRTH,MOBIRTH,DABIRTH))/365.25.
• The CTIME.MINUTES function converts a time interval to number of minutes. If HR equals
12, MIN equals 30, and SEC equals 30, the TIME.HMS function returns an interval of
45,030, which CTIME.MINUTES converts to minutes. NMINS equals 750.50.
• The YRMODA function converts the current date (in this example, October 1, 1992) and
birthdate to a number of days. The birthdate is subtracted from the current date and the
remainder is divided by the number of days in a year to yield the age in years.
Date and Time Extraction Functions
COMPUTE MONTHNUM=XDATE.MONTH(BIRTHDAY).
COMPUTE DAYNUM=XDATE.JDAY(BIRTHDAY).
• The XDATE.MONTH function reads a date and returns the month number expressed as an
integer from 1 to 12. If BIRTHDAY is formatted as DATETIME20 and contains the value
05-DEC-1954 5:30:15, MONTHNUM equals 12.
• The XDATE.JDAY function returns the day of the year, expressed as an integer between 1
and 366. For the value BIRTHDAY used by the first COMPUTE, DAYNUM equals 339.