how to change gender factor into an numerical coding in r

问题

I have a factor of males and females say c("male", "female","female") and I want to create a vector of c(0,1,1) How can i change that in r?

回答1:

With boolean :

a <- c("male", "female","female")
(a=="female")*1

hth

回答2:

Maybe not the most straight-forward way, but I would first change it to a factor, and then, if needed to an integer:

a <- c("male", "female","female")
a <- factor(a, levels=c("male","female"), labels=c(0,1))
a
[1] 0 1 1
Levels: 0 1

as.integer(as.character(a)) #Need to be first transformed to a character 
[1] 0 1 1                   #and then to an integer

来源：https://stackoverflow.com/questions/19313862/how-to-change-gender-factor-into-an-numerical-coding-in-r