grep()来搜索数据帧的列名

Question

有更清晰,更简单,更直接,更短的方式来做到这一点:

其中df1是数据帧:

names(df1[grep("Yield",names(df1))])

我想返回任何包含单词yield的列名.

谢谢,

Answer 1

grep有一个value应该适用于此的论据.尝试:

grep("Yield", names(df1), value = TRUE)

MRE

df1 <- data.frame(
  Yield_1995 = 1:5,
  Yield_1996 = 6:10,
  Something = letters[1:5]
)

## Your current approach
names(df1[grep("Yield",names(df1))])
# [1] "Yield_1995" "Yield_1996"

## My suggestion
grep("Yield", names(df1), value=TRUE)
# [1] "Yield_1995" "Yield_1996"

好的,所以它在简洁方面没有赢,但它确实意图的明确性:-)

为了多样化......一种"dplyr"的方法.

library(dplyr)
names(df1 %>% select(contains("Yield")))
# [1] "Yield_1995" "Yield_1996"
names(select(df1, contains("Yield")))
# [1] "Yield_1995" "Yield_1996"