将后缀设置为前缀

Question

df <- data.frame(
  home_loc   = rnorm(5),
  work_loc   = rnorm(5),
  x1         = rnorm(5),
  walk_act   = rnorm(5),
  bike_act   = rnorm(5),
  x2         = rnorm(5),
  happy_yest = rnorm(5),
  sad_yest   = rnorm(5)
)

suff_to_pre <- function(x, suffix, prefix) {
  for (i in seq_along(names(x))) {
    if (grepl(suffix, names(x)[i])) {
      names(x)[i] <- sub(suffix, "", names(x)[i])
      names(x)[i] <- paste0(prefix, names(x)[i])
    }
  }
  names(x)
}

names(df) <- suff_to_pre(df, suffix = "_loc", prefix = "loc_")
names(df) <- suff_to_pre(df, suffix = "_act", prefix = "act_")
names(df) <- suff_to_pre(df, suffix = "_yest", prefix = "yest_")

names(df)
[1] "loc_home" "loc_work" "x1" "act_walk" "act_bike" "x2" "yest_happy"
[8] "yest_sad"

a <- df %>%
  select(ends_with("_loc")) %>%
  setNames(sub("_loc", "", names(.))) %>%
  setNames(paste0("loc_", names(.)))

b <- df %>%
  select(ends_with("_act")) %>%
  setNames(sub("_act", "", names(.))) %>%
  setNames(paste0("act_", names(.)))

c <- df %>%
  select(ends_with("_yest")) %>%
  setNames(sub("_yest", "", names(.))) %>%
  setNames(paste0("yest_", names(.)))

df <- cbind(
  select(df, x1, x2), a, b, c
)

df <- data.frame(
      home_loc   = rnorm(5),
      work_loc   = rnorm(5),
      x_1        = rnorm(5),
      walk_act   = rnorm(5),
      bike_act   = rnorm(5),
      x_2        = rnorm(5),
      happy_yest = rnorm(5),
      sad_yest   = rnorm(5),
      free_time  = rnorm(5)
)

Answer 1

单个sub调用就足够了：

sub("^(.*)_(.*)$", "\\2_\\1", names(df))
#[1] "loc_home"   "loc_work"   "x1"         "act_walk"   "act_bike"   "x2"         "yest_happy" "yest_sad" 

当然，要更改名称，请将其分配回来：

names(df) <- sub("^(.*)_(.*)$", "\\2_\\1", names(df))

在dplyr-pipe中，您可以使用setnames:

df %>% setNames(sub("^(.*)_(.*)$", "\\2_\\1", names(.)))

suf <- c("act", "loc", "yest")

2）基于后缀创建正则表达式模式：

pat <- paste0("^(.*)_(", paste(suf, collapse = "|"), ")$")
pat
#[1] "^(.*)_(act|loc|yest)$"

3）照旧进行：

sub(pat, "\\2_\\1", names(df))
# [1] "loc_home"   "loc_work"   "x_1"        "act_walk"   "act_bike"   "x_2"        "yest_happy" "yest_sad"   "free_time" 

或

df %>% setNames(sub(pat, "\\2_\\1", names(.)))