I need to create a factor variable in Rstudio to separate data into categories and then add to data frame?

Question

So I have come up with this code so far but have now run into errors getting spit out back at me. I am trying to separate this dataset into weight groups listed <60, 60-70, >70 and then add it back to my data frame. I am a beginner too, so I think I did something wrong here.

runif(50, 55, 80)
rnorm(50, 176, 6)
runif(50, 65, 100)
DF <- data.frame(Height = rnorm(50, 170, 5),
                 Weight = rnorm(50, 55, 5))

weight.group = factor(NA, levels = c("0-60", "61-70", "71+"))
idx = which(rnorm <= 60)
weight.group[idx] = rep("0-60", length(idx))
idx = which(weight = 61 - 70)
weight.group[idx] = rep("61-70", length(idx))
idx = which(weight >= 71)
weight.group[idx] = rep("71+", length(idx))

Looks like you accidentally deleted the code you are referrng to in your question. I undid that for you. Please leave the questions complete and answerable, even if you got an answer. — Yunnosch, Sep 26 '21 at 20:55

Vinícius Félix · Answer 1 · 2021-09-26T17:42:58.550

1

Tidyverse

library(dplyr)

DF %>% 
  mutate(weight_group  = cut(
           x = Weight,
           breaks = c(0,60,70,Inf),
           include.lowest = TRUE,
           labels = c("0-60", "61-70", "71+")
   )
  )

Base

DF$weight_group <- 
  cut(
    x = DF$Weight,
    breaks = c(0,60,70,Inf),
    include.lowest = TRUE,
    labels = c("0-60", "61-70", "71+")
  )

Result

     Height   Weight weight_group
1  166.0988 53.31766         0-60
2  171.2802 68.57363        61-70
3  164.1006 54.34834         0-60
4  173.4387 61.23054        61-70
5  167.6080 63.13028        61-70
...

edited Sep 26 '21 at 17:42

answered Sep 26 '21 at 16:29

Vinícius Félix

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I find the label `"61-70"` misleading, it's in fact an left-open interval `(60, 70]`. But upvote. – Rui Barradas Sep 26 '21 at 16:34
Updated my answer @Alfred with a pure base solution – Vinícius Félix Sep 26 '21 at 17:43
Thanks. How would I insert this into existing dataset? Also, how can I split participants into 2 groups? BMI above and below average? – Not a Wrench Sep 26 '21 at 18:08
The code already insert in the dataset. You could also use the same logic to create a new variable, or use an `ifelse` – Vinícius Félix Sep 26 '21 at 18:11
OK. Did you get what I as trying to do with the original weight.group things? I want to understand what's the reason I am running into issues there for future reference. – Not a Wrench Sep 26 '21 at 23:05

I need to create a factor variable in Rstudio to separate data into categories and then add to data frame?

1 Answers1

Tidyverse

Base

Result