Message-ID: <403F6EC7.1070809@statistik.uni-dortmund.de>
Date: 2004-02-27T16:22:31Z
From: Uwe Ligges
Subject: question
In-Reply-To: <20040227095630.59042268.svetlana.eden@vanderbilt.edu>
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