-1
以下数据集:提取塔值
df <- read.table(text = " a b c
X Y Z", header = T)
命令
df[, sapply (df[1, ], as.character) %in% c("Y", "X")]
回报
a b
1 X Y
但命令
df[, sapply (df[1, ], as.character) %in% c("Y")]
个
回报
[1] Y
Levels: Y
,而不是
b
1 Y
任何想法,为什么?我怎样才能获取正确的列名
使用'下降= FALSE'在'[.data.frame',即'DF [,sapply(DF [1],as.character )%c(“Y”),drop = FALSE]' – jogo
相关,(可能重复)http://stackoverflow.com/questions/36499666/subsetting-datafram-based-on-row-value回答@RomanLuštrik – zx8754
[一般禁用矩阵的维度删除?]可能的重复(http://stackoverflow.com/questions/12196724/generally-disable-dimension-dropping-for-matrices) – jogo