想知道下面是一個錯誤正確答案......爲了不使後map_dbl
數據幀
df <- data.frame(Name=rep(letters[1:3],each=3), Value=c(20,40,35,70,80,90,10,20,30))
一些操作
library(tidyverse)
df1 <- split(df, df$Name) %>%
map(., ~.x %>% arrange(desc(Value)))
df2 <- map_dbl(df1, ~head(.x$Value, 1))
--LOOK AT DATA
head(df2)
a b c
40 90 30
str(df2)
Named num [1:3] 40 90 30
- attr(*, "names")= chr [1:3] "a" "b" "c"
--BUG?
order(df2)
[1] 3 1 2
給出不正確的答案,但
df2['a'] > df2['c']
TRUE
給出正確的答案。難道我做錯了什麼?
@我的回答是否清楚? – Wen