R help - Dec 2024 - Weird Behavior of mean

I've not checked the code, but I think that result would happen if mean
uses something like

if (na.rm == TRUE) {
  # do something to remove the NA's
}

And as uses something like

If (na.rm != FALSE) {
  # do something to remove the NA's
}

Or perhaps ever na.rm == T


If you ever see posts from Bert on here with T and F, he is hard core
thorough and uses full words for exactly this reason, someone can reassign
F as True if they want and your code will melt!

On Fri, 13 Dec 2024, 08:31 Ivo Welch, <ivo.welch at gmail.com> wrote:
> Is the following a strange behavior for `mean` vs. `sd` ?
>
> ```
> $ R --vanilla. ## 4.4.2
> > x=c(NA,1,2,3)
> > c( mean(x,na.rm=T), sd(x,na.rm=T) )
> [1] 2 1
> > T=20   ## bad idea for a parameter.  T is also used for TRUE
> > c( mean(x,na.rm=T), sd(x,na.rm=T) )
> [1] NA  1
> >
> ```
>
> This one was a baffler for me to track down for a few hours...
>
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> https://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
	[[alternative HTML version deleted]]

>>>>> CALUM POLWART 
>>>>>     on Fri, 13 Dec 2024 08:56:15 +0000 writes:
    > I've not checked the code, but I think that result would
    > happen if mean uses something like

    > if (na.rm == TRUE) { # do something to remove the NA's }

    > And as uses something like

    > If (na.rm != FALSE) { # do something to remove the NA's }

    > Or perhaps ever na.rm == T

Hey, "be careful you are insulting" (;-) R core code would *never*
contain stupid silly code
such as   <logical> == TRUE 

> fortunes :: fortune("TRUE.*TRUE", fixed=FALSE)
Ted Harding: But you can also do these with 'any' and 'all',
e.g. any(v==TRUE).
Thomas Lumley: or any( (v==TRUE)==TRUE), or any( ((v==TRUE)==TRUE)==TRUE)... Or,
perhaps, any(v). Lewis Carroll wrote a nice piece
on this theme.
   -- Ted Harding and Thomas Lumley (about implementing an 'or' of a
logical vector)
      R-help (August 2004)

It uses  if(isTRUE(na.rm))
and yes,
people using  T  for TRUE  are "selber tschuld" (Swiss German for
"your fault!")

Martin


    > If you ever see posts from Bert on here with T and F, he
    > is hard core thorough and uses full words for exactly this
    > reason, someone can reassign F as True if they want and
    > your code will melt!

    > On Fri, 13 Dec 2024, 08:31 Ivo Welch,
    > <ivo.welch at gmail.com> wrote:

    >> Is the following a strange behavior for `mean` vs. `sd` ?
    >> 
    >> ``` $ R --vanilla. ## 4.4.2 > x=c(NA,1,2,3) > c(
    >> mean(x,na.rm=T), sd(x,na.rm=T) ) [1] 2 1 > T=20 ## bad
    >> idea for a parameter.  T is also used for TRUE > c(
    >> mean(x,na.rm=T), sd(x,na.rm=T) ) [1] NA 1
    >> >
    >> ```
    >> 
    >> This one was a baffler for me to track down for a few
    >> hours...
    >> 
    >> ______________________________________________
    >> R-help at r-project.org mailing list -- To UNSUBSCRIBE and
    >> more, see https://stat.ethz.ch/mailman/listinfo/r-help
    >> PLEASE do read the posting guide
    >> https://www.R-project.org/posting-guide.html and provide
    >> commented, minimal, self-contained, reproducible code.
    >> 

    > 	[[alternative HTML version deleted]]

    > ______________________________________________
    > R-help at r-project.org mailing list -- To UNSUBSCRIBE and
    > more, see https://stat.ethz.ch/mailman/listinfo/r-help
    > PLEASE do read the posting guide
    > https://www.R-project.org/posting-guide.html and provide
    > commented, minimal, self-contained, reproducible code.