Date:         Thu, 3 Jun 2004 13:10:43 +0200
Reply-To:     "Groeneveld, Jim" <jim.groeneveld@VITATRON.COM>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         "Groeneveld, Jim" <jim.groeneveld@VITATRON.COM>
Subject:      Re: Q: looping nested format
Comments: To: julierog@ix.netcom.com, trovato@verizon.net
Content-Type: text/plain; charset="iso-8859-1"

Hi Roger,

Yes, I already feared something like that. Thanks.

Regards - Jim.
--
.  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .

Jim Groeneveld, MSc.
Biostatistician
Science Team
Vitatron B.V.
Meander 1051
6825 MJ  Arnhem
Tel: +31/0 26 376 7365
Fax: +31/0 26 376 7305
Jim.Groeneveld@Vitatron.com
www.vitatron.com

My computer may have missed me, I did not; it, that is.

[common disclaimer]


-----Original Message-----
From: Roger Lustig [mailto:trovato@verizon.net]
Sent: Thursday, June 03, 2004 13:02
To: Groeneveld, Jim
Subject: Re: Q: looping nested format


Jim:
The reason is that, when you specify a nested format in your VALUE
statement, SAS does nothing at all!  Only when the format is *called*
does SAS go looking for a format to resolve the nesting.  And since
you've specified exactly one format (that would be $NestFmt. --
specifying widths doesn't make new formats), SAS finds what you
specified, sees that it needs resolving, looks for $NestFmt. again, sees
that it needs resolving, etc.

Try this:

proc format;
value test
low-high=[Zonk16.]
;
run;

No error message, even though the Zonk. format doesn't exist.  Now try
*using* the format.

Roger

Groeneveld, Jim wrote:
> Hi friends,
>
> Why does the following nested format loop so many times that its stack space gets full?
> I explicitly specified it to loop 11 times at maximum. I would like to hear your opinions.
> Mine is that apparently SAS does not initially look at the format lengths and thus iterates indefinitely (if it could).
>
> 1          PROC FORMAT;
> 2            VALUE $NestFmt
> 3            '11111111111' = [$NestFmt10.]
> 4            '1111111111' = [$NestFmt9.]
> 5            '111111111' = [$NestFmt8.]
> 6            '11111111' = [$NestFmt7.]
> 7            '1111111' = [$NestFmt6.]
> 8            '111111' = [$NestFmt5.]
> 9            '11111' = [$NestFmt4.]
> 10           '1111' = [$NestFmt3.]
> 11           '111' = [$NestFmt2.]
> 12           '11' = [$NestFmt1.]
> 13           '1' = [$1.]
> 14           ;
> NOTE: Format $NESTFMT has been output.
> 15         RUN;
>
> NOTE: PROCEDURE FORMAT used:
>       real time           0.15 seconds
>       cpu time            0.01 seconds
>
> 16
> ERROR:  Stack overflow detected In Task ( DATASTEP ]
> ERROR:  Stack overflow detected In Task ( DATASTEP ]
> ERROR:  Stack overflow detected In Task ( DATASTEP ]
> Exception occurred at (67996E49)
> Exception occurred at (67996E49)
> Exception occurred at (67996E49)
> Task Traceback
> Task Traceback
> Task Traceback
>
>  NOTE: DATA statement used:
>       real time           3.77 seconds
>       cpu time            3.61 seconds
>
> 17         DATA NestFmt / DEBUG;
> 18           x = '11111111111'; * but the value does not influence the error result;
> 19           FORMAT X $NestFmt12.;
>
> 20         RUN;
> 21
> 22         PROC PRINT DATA=NestFmt; RUN;
> ERROR: File WORK.NESTFMT.DATA does not exist.
> ERROR: File WORK.NESTFMT.DATA does not exist.
> ERROR: File WORK.NESTFMT.DATA does not exist.
>
> Regards - Jim.
> --
> .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .
>
> Jim Groeneveld, MSc.
> Biostatistician
> Science Team
> Vitatron B.V.
> Meander 1051
> 6825 MJ  Arnhem
> Tel: +31/0 26 376 7365
> Fax: +31/0 26 376 7305
> Jim.Groeneveld@Vitatron.com
> www.vitatron.com
>
> My computer may have missed me, I did not; it, that is.
>
> [common disclaimer]