Date: Thu, 4 Dec 2003 12:17:42 -0500
Reply-To: Ian Whitlock <WHITLOI1@WESTAT.COM>
Sender: "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From: Ian Whitlock <WHITLOI1@WESTAT.COM>
Subject: Re: Debugging SAS with many variables (newbie)
Content-Type: text/plain
Carl,
The ideal solution is to use the file layout specification as control data
to generate the INPUT statement. Then it will be as correct as the
specification is. If you can post a sample of what the layout looks like
and in what form it is electronically stored, someone can probably give you
very good advice.
The DUMP is produced by the LIST command and PUT _ALL_. These commands are
triggered by having the automatic variable _ERROR_ set to 1. The order of
variables in the dump and on the SAS dataset is controlled by their order of
appearance in the creating DATA step. Usually this means the dump will be
in the order of the variables in the INPUT statement. Since it is not true
for you there must be other statements preceding the INPUT statement. One
of your requests could be satisfied by ordering the variables correctly in
those statements.
However there may be a simpler solution. Let's suppose you have
input x 3. a $char5. z 8. ;
You could copy that statement in a text editor and remove everything but the
variable names. In the example the result is
x a z
You could then add RETAIN at the beginning and a semicolon at the end.
retain x a z ;
This statement could then be made the first line of the DATA step. It will
force the order of variables in the dump without prejudicing the variable
type. However, it has a side affect that the variables named will not
automatically be set to missing. This may or may not cause problems with
the logic of your DATA step so it would probably be good to remove this
line, once you have finished debugging.
Here is an example illustrating a way to easily obtain an alphabetic order.
data w ; /* copy of your input data step */
infile cards obs = 1 ; /* modified INFILE */
input x y a ;
cards ;
1 2 3
4 5 6
7 8 9
;
proc contents data = w out=c(keep = name) noprint ;
run ;
proc sql noprint ;
select name into :varlist separated by " "
from c
;
quit ;
data w ; /* your real input data step for debugging */
retain &varlist ; /* inserted RETAIN statement */
input x y a ;
cards ;
1 2 3
;
The SQL step creates what is called a macro variable. In this case VARLIST.
It holds the whole column of variable names. (In version 8.2 it can be up
to 64K long, so you probably will have plenty of room unless you INPUT
statement is more than 100+ pages long.) The & in the RETAIN statement is a
reference to this macro variable. If you want to see the value add
options symbolgen ;
in front of the input DATA step, or use
%put &varlist ;
I have illustrated with CARDS so that anyone could execute the code. Your
input DATA step will be much longer and more complex but it shouldn't make
any difference, the principle is the same.
IanWhitlock@westat.com
-----Original Message-----
From: Carl Kyonka [mailto:Carl.Kyonka@ENBRIDGE.COM]
Sent: Thursday, December 04, 2003 10:39 AM
To: SAS-L@LISTSERV.UGA.EDU
Subject: Debugging SAS with many variables (newbie)
I have a file with mixed numeric and alphabetic variables. I am slogging my
way through writing an INPUT statement to read these records. I get errors
with a somewhat helpful dump of the input record and the variables as they
stand when an error occurred. My difficulty is that there are lots of
variables and finding the ones I want is awkward. I can use the find command
to locate each variable in the sequence they are listed in the INPUT
statement, but that is time-consuming. This may be well documented, but I do
not know what to call this record dump so I have not found it in on-line
doc. What I would like is an option to sort the variables being dumped
either alphabetically or in the INPUT sequence. Or a tactic to help
debugging the INPUT statement. Thanks for the time, Carl Kyonka
