Re: SAS 8 vs. 9 incompatibility

Now, try it with a special missing value ...

DATA _NULL_;
MisMis = ._ EQ -._; * -. is not the missing value ._;
MisMis0 = 0 * (._ EQ -._); * and neither the Morse code for N;
MisMis1 = 1 * (._ EQ -._); * it is: minus the missing value .;
PUT (_ALL_)(=);
RUN;

In SAS 9.1.3, WinXP, produces:
MisMis=0 MisMis0=0 MisMis1=0

As a clue, it also produces:
NOTE: Missing values were generated as a result of performing an
operation on missing values.

In terms of "the meaning of a negative missing value" -- the minus sign
(-) is an operator, just as the * and EQ are. Attempting to perform an
arithmetic operation such as negation on any missing value results in a
"standard" missing value (.). In SAS, however, the result of an
equality test is always true or false (1 or 0).

Mike Rhoads
Westat
RhoadsM1@Westat.com



-----Original Message-----
From: owner-sas-l@listserv.uga.edu [mailtowner-sas-l@listserv.uga.edu]
On Behalf Of Jim Groeneveld
Sent: Wednesday, June 28, 2006 10:13 AM
To: SAS-L@LISTSERV.UGA.EDU
Cc: Jim Groeneveld
Subject: SAS 8 vs. 9 incompatibility


Hi friends,

Run the following test program in both SAS vs. 8 and SAS vs. 9 if you
can
and have a look at the difference.

DATA _NULL_;
MisMis = . EQ -.; * -. is not the missing value ._;
MisMis0 = 0 * (. EQ -.); * and neither the Morse code for N;
MisMis1 = 1 * (. EQ -.); * it is: minus the missing value .;
PUT (_ALL_)(=);
RUN;

SAS vs. 8 yields:
MISMIS=1 MISMIS0=. MISMIS1=.
while SAS vs. 9 yields:
MISMIS=1 MISMIS0=0 MISMIS1=1

You could question the meaning of a negative missing value, but given
the
first value I think SAS vs. 9 is correct with the two other values and
SAS
vs. 8 is not.

Where I work now (on secondment) they changed from SAS 8 to SAS 9 today.

Regards - Jim.
--
Jim Groeneveld, Netherlands
Statistician, SAS consultant
home.hccnet.nl/jim.groeneveld