Date:         Fri, 20 Jun 1997 01:23:01 +0100
Reply-To:     John Whittington <johnw@MAG-NET.CO.UK>
Sender:       "SAS(r) Discussion" <SAS-L@UGA.CC.UGA.EDU>
From:         John Whittington <johnw@MAG-NET.CO.UK>
Subject:      Re: FW: data step bug
Comments: To: david.yeates@health-care-epidemiology.oxford.ac.uk
Content-Type: text/plain; charset="us-ascii"

On Thu, 19 Jun 1997, David Yeates
<david.yeates@health-care-epidemiology.oxford.ac.uk> wrote:
 
>as stated it is perfectly logical to get the answer ?? as the comparison
>is being carried out on strings of differing lengths.
 
David, although much of what you say is true, I think you may be missing the
point.  No matter what the values of X and Y, and no matter what the
mechanics of the comparison operation, the two conditions (X GT Y) and (X LT
Y) have got to be mutually exclusive.
 
Accordingly, unless I'm missing something, any software which gives the same
test result for (X GT Y) and (X LT Y) - for *any* values of X and Y - has
got to be in error, at least in terms of logic.
 
Regards,
 
 
John
 
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