magrittr_example.R

# convert c("female", "Male") to c(0,1)

# magrittr is way nicer than nested function calls

convert_sexcodes <-
function(codes)
{
    require(magrittr)

    tolower(codes) %>%
        substr(., 1, 1) %>%
        match(., c("f", "m")) - 1
}

convert_sexcodes_old <-
function(codes)
{
    match(substr(tolower(codes), 1, 1), c("f", "m")) - 1
}

Pipestravaganza:

convert_sexcodes <- function(codes) {
  codes %>%
    tolower() %>%
    substr(1, 1) %>%
    match(c("f", "m")) %>%
    `-`(1)
}

Or: car::recode(codes, "'Female'=0;'Male'=1")

Or revalue() from (d)plyr:

x <- c('Female', 'male', 'Male', 'female')
x %>% tolower %>% revalue(c(female = 0, male = 1)) %>% as.numeric

Thanks to you all!

Base R has a lot of good functions.

codes <- ifelse(codes == "Male", 1, 0)