Dear R-users,
i try to recode a factor according to old levels
F <- factor(sample(c(rep("A", 4), rep("B",2),
rep("C",5))))
recode(F, "levels(F)[c(1,3)]='X'; else='Y'")
i tried to work with eval or expression around levels(F)[c(1,3)], but
nothing seems to work.
Many thanks if anyone could tell me what i've missed and what's the
problem here.
best regards
Andreas
Hi r-help-bounces at r-project.org napsal dne 18.11.2009 09:24:40:> Dear R-users, > > i try to recode a factor according to old levels > > F <- factor(sample(c(rep("A", 4), rep("B",2), rep("C",5)))) > > recode(F, "levels(F)[c(1,3)]='X'; else='Y'") > > i tried to work with eval or expression around levels(F)[c(1,3)], but > nothing seems to work. >I am not sure if recode does not want as an input a numeric vector. However for recoding levels of factor you can add a vector of new levels in correct order. set.seed(111) F <- factor(sample(c(rep("A", 4), rep("B",2), rep("C",5)))) levels(F)<-c("X","X","Y") F [1] Y Y X X X Y X X X Y Y Levels: X Y or maybe levels(F)<- ifelse(levels(F) %in% c("A","B"), "X", "Y") Regards Petr> > Many thanks if anyone could tell me what i've missed and what's the > problem here. > > best regards > > Andreas > > ______________________________________________ > R-help at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guidehttp://www.R-project.org/posting-guide.html> and provide commented, minimal, self-contained, reproducible code.
Andreas Wittmann wrote:> Dear R-users, > > i try to recode a factor according to old levels > > F <- factor(sample(c(rep("A", 4), rep("B",2), rep("C",5)))) > > recode(F, "levels(F)[c(1,3)]='X'; else='Y'") > > i tried to work with eval or expression around levels(F)[c(1,3)], but > nothing seems to work. >I assume that you mean the recode() function in pkg:car? (You really should say so.) Here are a couple of ways to recode the factor: set.seed(6931) F <- factor(sample(rep(c("A","B","C"), c(4,2,5)))) lev <- levels(F) # 1: using car:::recode F <- recode(F, "lev[c(1,3)] = 'X'; else = 'Y'") # 2: using base:::levels levels(F) <- list(X = lev[c(1,3)], Y = lev[-c(1,3)]) -Peter Ehlers> > Many thanks if anyone could tell me what i've missed and what's the > problem here. > > best regards > > Andreas > > ______________________________________________ > R-help at r-project.org mailing list > 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. > >