[R] question

[Uwe Ligges]

Svetlana Eden wrote:

> Hi everybody.
> 
> The question:
> I get two vectors 'iFalseFalse' and 'i2'.
> I think they should be the same but they are not.
> Is it because 
> R does not handle complicated logical expressions in such cases 
> or I do something wrong?
> 
> 
> 
>>z1 = c(NA, "", 3, NA, "", 3)
>>z2 = c("", "", 3, NA, 3, NA)
>>cV = (as.character(z1)==as.character(z2))
>>cV
> 
> [1]    NA  TRUE  TRUE    NA FALSE    NA
> 
>>iFalse = (c(1:(length(z1))))[(cV==FALSE)]
>>iNonNA = (c(1:(length(z1))))[(!(is.na(cV)))]
>>iFalse
> 
> [1] NA NA  5 NA
> 
>>iNonNA
> 
> [1] 2 3 5
> 
>>iFalseFalse = intersect(iFalse, iNonNA)
>>iFalseFalse
> 
> [1] 5
> 
>>i2 = (c(1:(length(z1))))[( (cV==FALSE)&&(!(is.na(cV))) )]
>>i2
> 
> numeric(0)
> 
> 

Each line's results as expected.
In the last line, you are going to use "&" instead of "&&"!

Uwe Ligges