why my new var name show up as "... <- NULL"

Question

I would like to creat a var named"AGEGROUP" for age group. I wrote following code. But it seems like the new variable name in the data set show up as "... <- NULL" instead of "AGEGROUP". Why? How should I fix this.

Here is my codes:

set.seed(12345)
AGE <- sample(0:110, 100, replace = TRUE)
Sample.data <-data.frame(AGE)

Sample.data <- Sample.data %>% dplyr::mutate(AGEGROUP <-cut(AGE,
                                              right=FALSE,
                                              breaks = c(0,1,12,17,64,1000),
                                              labels = c("Infant(0.083-1.999 yrs)","Child(2-12.999 yrs)", "Adolescent(13-17.999 yrs)","Adult(18-64.999 yrs.)","Elderly(65-199 yrs)")))

Answer 1

There seems to be a <- (assignment) instead of "=" (parameter match):

library("dplyr")

set.seed(12345)
AGE <- sample(0:110, 100, replace = TRUE)
Sample.data <-data.frame(AGE)

Sample.data <- Sample.data %>%
  dplyr::mutate(AGEGROUP = cut(
    AGE,
    right = FALSE,
    breaks = c(0, 1, 12, 17, 64, 1000),
    labels = c(
      "Infant(0.083-1.999 yrs)",
      "Child(2-12.999 yrs)",
      "Adolescent(13-17.999 yrs)",
      "Adult(18-64.999 yrs.)",
      "Elderly(65-199 yrs)"
    )
  ))