Working with factors and numbers

#working with factors

>data=c(1,2,3,2,2,3,1,1,3,4,4,3)

>fdata=factor(data)

>fdata

>table (fdata)

#assigning label to a factor variable

>rdata=factor(data,labels=c('I','II','III','IV'))

>rdata

>table (rdata)

#Example using retinol data>retinol$tabac=factor(retinol$tabac, labels=c("Never", "Ex", "Current"))

#transforming an object into factor is necessary so that R treats it as a categorical variable

varname=as.factor(varname)

#transforming string to numeric

names=c("donald", "mickey", "pluto")

names_fact=as.factor(names)

names_fact

names_num=as.numeric(names_fact)

names_num