Date:         Thu, 4 May 2006 17:41:57 -0700
Reply-To:     Jack Hamilton <jfh@STANFORDALUMNI.ORG>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Jack Hamilton <jfh@STANFORDALUMNI.ORG>
Subject:      Re: Getting PROC SQL to emulate PROC SORT NODUPKEY
Comments: To: Sigurd Hermansen <HERMANS1@WESTAT.COM>
In-Reply-To:  <CA8F89971ADA9F47A6C915BA239784421B3627@MAILBE2.westat.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

On 5/5/2006 7:52 AM Sigurd Hermansen said the following:
> Scott:
> A SAS format implements a function. By definition, a function f(a,b)
> yields the same value of b for any instance of a distinct value of a.

Just to quibble, I'd say they implement relations, not functions.
There's no restriction on either SAS formats or SAS functions that they
return a single output value for any given input value.  Multi-label
formats are a counterexample of the former, and the random functions are
a counterexample of the latter.