Question

如何按名称选择多个列，而无需键入每个名称。

例如，我有以下代码：

CTDB[, c(
"ENJOY_TV_RADIO_CHILD", 
"ENJOY_FMLY_CLOSE_FRND_CHILD", 
"ENJOY_HOBBIES_CHILD", 
"ENJOY_FAV_MEAL_CHILD",
"ENJOY_SHOWER_CHILD", 
"ENJOY_SCENT_CHILD", 
"ENJOY_PPL_SMILE_CHILD", 
"ENJOY_LOOK_SMART_CHILD", 
"ENJOY_READ_CHILD", 
"ENJOY_FAV_DRINK_CHILD", 
"ENJOY_SMALL_THINGS_CHILD", 
"ENJOY_LANDSCAPE_CHILD", 
"ENJOY_HELP_OTHR_CHILD", 
"ENJOY_PRAISE_CHILD")] <-revalue(as.matrix(CTDB[, c(
"ENJOY_TV_RADIO_CHILD", 
"ENJOY_FMLY_CLOSE_FRND_CHILD",
"ENJOY_HOBBIES_CHILD", 
"ENJOY_FAV_MEAL_CHILD", 
"ENJOY_SHOWER_CHILD", 
"ENJOY_SCENT_CHILD", 
"ENJOY_PPL_SMILE_CHILD", 
"ENJOY_LOOK_SMART_CHILD", 
"ENJOY_READ_CHILD", '
"ENJOY_FAV_DRINK_CHILD", 
"ENJOY_SMALL_THINGS_CHILD", 
"ENJOY_LANDSCAPE_CHILD", 
"ENJOY_HELP_OTHR_CHILD", 
"ENJOY_PRAISE_CHILD")]), c("0"=3, "1"=2, "2"=1, "3"=0))

所有列都按顺序排列，而不是按照下面的数字选择

CTDB[,74:87] <-revalue(as.matrix(CTDB[,74:87]), c("0"=3, "1"=2, "2"=1, "3"=0))

我想通过列名来选择。

谢谢！

Answer 1

您应该使用grep或grepl

CTBD[,grep("^ENJOY.*CHILD$",colnames(CTBD)]

或

CTBD[,grepl("^ENJOY.*CHILD$",colnames(CTBD)]

Answer 2

如果您需要将此作为管道的一部分，您还可以使用dplyr::select及其辅助函数以两种等效方式使用，包括可以避免使用正则表达式的方法：

CTBD %>% select(matches("^ENJOY.*CHILD$"))
CTBD %>% select(intersect(starts_with("ENJOY"), ends_with("CHILD")))

按名称选择多个列，而无需键入每个名称

2 个答案: