okrągłe wiele kolumn w R

# load dplyr
library(dplyr)

# Round at first decimal with a mixed df
mydf %>% mutate(across(where(is.numeric), round, 1))

# The two solutions above do the same
mydf %>% mutate(across(where(is.numeric), ~round(., 1)))
mydf %>% mutate_if(is.numeric, round, 1)
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