Subset n number of rows from a dataframe, based on a categorical variable, in R -

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i have dataframe (say x) in r:

> x height  weight gender 5     60    m 5     70    m 6     80    m 4     90    m 4     60    m 5     70    f 5     80    f 6     60    f 4     90    f 4     60    f

i need r code produce new dataframe, y, takes subset of x gender , first 3 rows of each gender (1:3) give result follows.

>y height  weight gender 5       60      m 5       70      m 6       80      m 5       70      f 5       80      f 6       60      f

try slice dplyr

library(dplyr) x %>%     group_by(gender) %>%      slice(1:3)

or using data.table

library(data.table) setdt(x)[,.sd[1:3] , gender]

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