mets (version 1.2.3.1)

drelevel: relev levels for data frames

Description

levels shows levels for variables in data frame, relevel relevels a factor in data.frame

Usage

drelevel(data, y = NULL, x = NULL, ref = NULL, newlevels = NULL,
  regex = mets.options()$regex, sep = NULL, overwrite = FALSE, ...)

Arguments

data

if x is formula or names for data frame then data frame is needed.

y

name of variable, or fomula, or names of variables on data frame.

x

name of variable, or fomula, or names of variables on data frame.

ref

new reference variable

newlevels

to combine levels of factor in data frame

regex

for regular expressions.

sep

seperator for naming of cut names.

overwrite

to overwrite variable

...

Optional additional arguments

Examples

# NOT RUN {
data(mena)
dstr(mena)
dfactor(mena)  <- ~twinnum
dnumeric(mena) <- ~twinnum.f

dstr(mena)

mena2 <- drelevel(mena,"cohort",ref="(1980,1982]")
mena2 <- drelevel(mena,~cohort,ref="(1980,1982]")
mena2 <- drelevel(mena,cohortII~cohort,ref="(1980,1982]")
dlevels(mena)
dlevels(mena2)
drelevel(mena,ref="(1975,1977]")  <-  ~cohort
drelevel(mena,ref="(1980,1982]")  <-  ~cohort
dlevels(mena,"coh*")
dtable(mena,"coh*",level=1)

### level 1 of zyg as baseline for new variable
drelevel(mena,ref=1) <- ~zyg
drelevel(mena,ref=c("DZ","[1973,1975]")) <- ~ zyg+cohort
drelevel(mena,ref=c("DZ","[1973,1975]")) <- zygdz+cohort.early~ zyg+cohort
### level 2 of zyg and cohort as baseline for new variables
drelevel(mena,ref=2) <- ~ zyg+cohort
dlevels(mena)

##################### combining factor levels with newlevels argument

dcut(mena,labels=c("I","II","III","IV")) <- cat4~agemena
dlevels(drelevel(mena,~cat4,newlevels=1:3))
dlevels(drelevel(mena,ncat4~cat4,newlevels=3:2))
drelevel(mena,newlevels=3:2) <- ncat4~cat4
dlevels(mena)

dlevels(drelevel(mena,nca4~cat4,newlevels=list(c(1,4),2:3)))

drelevel(mena,newlevels=list(c(1,4),2:3)) <- nca4..2 ~ cat4
dlevels(mena)

drelevel(mena,newlevels=list("I-III"=c("I","II","III"),"IV"="IV")) <- nca4..3 ~ cat4
dlevels(mena)

drelevel(mena,newlevels=list("I-III"=c("I","II","III"))) <- nca4..4 ~ cat4
dlevels(mena)

drelevel(mena,newlevels=list(group1=c("I","II","III"))) <- nca4..5 ~ cat4
dlevels(mena)

drelevel(mena,newlevels=list(g1=c("I","II","III"),g2="IV")) <- nca4..6 ~ cat4
dlevels(mena)

# }