R help - Jun 2016 - Error: missing value where TRUE/FALSE needed

Hi, 



I am getting the following error:

Error in if ((sum > 0 && sums1 > 0 && sums2 > 0) != NA)
{ :

missing value where TRUE/FALSE needed





I have including my code below for your review:



fitness_1_data 
	[[alternative HTML version deleted]]

Dear Shashi,

I don't see any code, but I will take a guess anyway:

The error tells you that you try to compare a boolean with something that
is not (TRUE or FALSE cannot be compared to NA).

HTH
Ulrik

On Thu, 9 Jun 2016 at 08:55 SHASHI SETH <sethshashi at rediffmail.com>
wrote:
> Hi,
>
>
>
> I am getting the following error:
>
> Error in if ((sum > 0 && sums1 > 0 && sums2 > 0)
!= NA) { :
>
> missing value where TRUE/FALSE needed
>
>
>
>
>
> I have including my code below for your review:
>
>
>
> fitness_1_data
>         [[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
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
	[[alternative HTML version deleted]]

Dear Shashi Seth,

The principal problem here is that the "argument" to if() must be
logical, while comparing anything to NA always produces NA. The proper way to
test for NA is with is.na().

There's potentially something more subtle going on here, however, which is
that even if some of the elements of the logical expression in the
"call" to if() are NA, the expression may evaluate to FALSE (but never
to TRUE) if the non-NA elements imply that it is FALSE. Consider the following
examples:
> TRUE && FALSE && NA  # FALSE regardless of the value of the
last element
[1] FALSE
> TRUE && TRUE && NA  # truth depends on the value of the
last element
[1] NA
> (TRUE && FALSE && NA) != NA
[1] NA
> (TRUE && TRUE && NA) != NA
[1] NA
> is.na(TRUE && FALSE && NA)
[1] FALSE
> is.na(TRUE && TRUE && NA)
[1] TRUE

I hope that this helps,
 John

-----------------------------
John Fox, Professor
McMaster University
Hamilton, Ontario
Canada L8S 4M4
Web: socserv.mcmaster.ca/jfox


> -----Original Message-----
> From: R-help [mailto:r-help-bounces at r-project.org] On Behalf Of SHASHI
SETH
> Sent: June 9, 2016 2:53 AM
> To: R-help at r-project.org
> Subject: [R] Error: missing value where TRUE/FALSE needed
> 
> Hi,
> 
> 
> 
> I am getting the following error:
> 
> Error in if ((sum > 0 && sums1 > 0 && sums2 > 0)
!= NA) { :
> 
> missing value where TRUE/FALSE needed
> 
> 
> 
> 
> 
> I have including my code below for your review:
> 
> 
> 
> fitness_1_data
> 	[[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 http://www.R-project.org/posting-
> guide.html
> and provide commented, minimal, self-contained, reproducible code.