Average data over several variables for several columns and store in data frame

Question

I want to get the mean for each diet and period. Then I would like to collect the answers for the columns score1, score2 and score3 in a data frame. I have run the function with aggregate. Do you know any other way to do this? just want to know for learning!

set.seed(8)
id <- 1:6
diet <- rep(c("A","B"),3)
period <- rep(c(1,2),3)
score1 <- sample(1:100,6)
score2 <- sample(1:100,6)
score3 <- sample(1:100,6)

df <- data.frame(id,diet,period,score1, score2, score3)

medel <- function(i){
  df <- aggregate(df[,i]~ period + diet, FUN=mean, data=df)
  df
}

I want it to be collected in a data frame like this:

    score1 score2   score3
1 52.33333     50 19.66667
2 51.33333     55 56.66667

`aggregate(.~diet+period, df, mean)` ? OR `df %>% group_by(diet, period) %>% summarise_all(mean)` using `dplyr`. — Ronak Shah, Feb 28 '20 at 08:23
`aggregate` option is base R, I am not sure what you are looking for. — Ronak Shah, Feb 28 '20 at 08:29
I was thinking something in a for loop, but maybe thats unnecessary, thanks! — user11916948, Feb 28 '20 at 08:42

score 1 · Accepted Answer · answered Feb 28 '20 at 08:27

1

One option would be to use dplyr:

df %>%
  select(-id) %>%
  group_by_at(vars(diet, period)) %>%
  summarise_all(~mean(.))

answered Feb 28 '20 at 08:27

AlexB

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Average data over several variables for several columns and store in data frame

1 Answers1