You want to use & instead of &&. --Matt
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Svetlana Eden Sent: Friday, February 27, 2004 7:57 AM To: r-help Subject: [R] question 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) > -- Svetlana Eden Biostatistician II School of Medicine Department of Biostatistics Vanderbilt University ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html