[R] [FORGED] Logical Operators' inconsistent Behavior

[peter dalgaard]

> On 19 May 2017, at 14:24 , Jérémie Juste <jeremiejuste at gmail.com> wrote:
> 
> My apologies if I was not clear enough,
> 
> TRUE & NA could be either TRUE or FALSE and consequently is NA.
> why is   FALSE & NA = FALSE?  NA could be TRUE or FALSE, so FALSE & NA
> should be NA?
> 

At the risk of flogging a dead horse:

FALSE & TRUE = FALSE
FALSE & FALSE = FALSE

FALSE & x = FALSE, whatever the value of x, hence 

FALSE & NA = FALSE

Get it?  

-pd


> 
> On Fri, May 19, 2017 at 2:13 PM, Rolf Turner <r.turner at auckland.ac.nz>
> wrote:
> 
>> On 20/05/17 00:01, Jérémie Juste wrote:
>> 
>>> Hello,
>>> 
>>> Rolf said,
>>> 
>>> TRUE & FALSE is FALSE but TRUE & TRUE is TRUE, so TRUE & NA could be
>>> either TRUE or FALSE and consequently is NA.
>>> 
>>> OTOH FALSE & (anything) is FALSE so FALSE & NA is FALSE.
>>> 
>>> 
>>> According to this logic why is
>>> 
>>>    FALSE & NA
>>> 
>>> [1] FALSE
>>> 
>> 
>> Huh????
>> 
>> 
>> cheers,
>> 
>> Rolf Turner
>> 
>> --
>> Technical Editor ANZJS
>> Department of Statistics
>> University of Auckland
>> Phone: +64-9-373-7599 ext. 88276
>> 
> 
> 
> 
> -- 
> Jérémie Juste
> 
> 	[[alternative HTML version deleted]]
> 
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-- 
Peter Dalgaard, Professor,
Center for Statistics, Copenhagen Business School
Solbjerg Plads 3, 2000 Frederiksberg, Denmark
Phone: (+45)38153501
Office: A 4.23
Email: pd.mes at cbs.dk  Priv: PDalgd at gmail.com