【发布时间】：2012-08-21 11:41:12
【问题描述】：
我正在尝试了解循环，我目前有一个很长的数据框列表，我需要进入一堆这些数据框并重命名一些变量。我有一个函数，但我正在努力构建一种智能的方式来遍历我的列表（实际列表比下面的示例长得多），同时应用不同的 suffixes 前缀 hen重命名。
希望我下面的工作示例能够说明这种情况。我想我可以将最后一部分构建成两个循环，但我似乎无法弄清楚如何在循环内写入列表中的数据框。
任何帮助将不胜感激！
data(mtcars)
mtcarsList <- list(mtcars1 = mtcars, mtcars2 = mtcars,
mtcarsA = mtcars, mtcars = mtcars )
# function I use to renames a specific number of variables
baRadd <- function(df, vector, suffix){
names(df) <- ifelse(names(df) %in% vector,names(df),
paste(suffix, names(df), sep = "."))
return(df)}
foo <- c("mpg", "cyl", "disp")
suffix1 <- "bar"
suffix2 <- "barBAR"
suffix3 <- "barBARbar"
mtcarsList$mtcars1 <- baRadd(mtcarsList$mtcars1, foo, suffix1)
mtcarsList$mtcars2 <- baRadd(mtcarsList$mtcars2, foo, suffix2)
mtcarsList$mtcarsA <- baRadd(mtcarsList$mtcarsA, foo, suffix3)
names(mtcarsList$mtcars1)
# [1] "mpg" "cyl" "disp" "bar.hp" "bar.drat" "bar.wt"
# [7] "bar.qsec" "bar.vs" "bar.am" "bar.gear" "bar.carb"
names(mtcarsList$mtcars2)
# [1] "mpg" "cyl" "disp" "barBAR.hp" "barBAR.drat"
# [6] "barBAR.wt" "barBAR.qsec" "barBAR.vs" "barBAR.am" "barBAR.gear"
# [11] "barBAR.carb"
names(mtcarsList$mtcarsA)
# [1] "mpg" "cyl" "disp" "barBARbar.hp"
# [5] "barBARbar.drat" "barBARbar.wt" "barBARbar.qsec" "barBARbar.vs"
# [9] "barBARbar.am" "barBARbar.gear" "barBARbar.carb"
names(mtcarsList$mtcars)
# [1] "mpg" "cyl" "disp" "hp" "drat" "wt" "qsec" "vs" "am" "gear"
# [11] "carb"
更新，
根据下面 DWin 的回复，我写了这个脚本来解决我的问题，
# rm(list = ls(all = TRUE)) ## Clear workspace
data(mtcars)
mtcarsList <- list(mtcars1 = mtcars, mtcars2 = mtcars,
mtcarsA = mtcars, mtcars = mtcars)
## function I use to renames a specific number of variables
baRadd <- function(df, vector, suffix){
names(df) <- ifelse(names(df) %in% vector,names(df),
paste(suffix, names(df), sep = "."))
return(df)}
suffixes <- c('A', 'B', 'C') # suffixes to be added to the three dfTO
whatNOTtoRename <- c("mpg", "cyl", "disp")
# variables within the data frame I do not want to renames
dfTO <- c('mtcars1','mtcars2','mtcarsA')
# the specific data frames I need to rename
# str(mtcarsList)
mtcarsList[ names( mtcarsList[dfTO]) ] <-
mapply(baRadd, df=mtcarsList[dfTO],
suffix= suffixes,
MoreArgs=list(vector=whatNOTtoRename) , SIMPLIFY=FALSE)
str(mtcarsList)
【问题讨论】：
-
这些看起来像前缀而不是后缀。
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@seancarmody，你说得对，前缀。感谢您指出这一点。
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当时我觉得很迂腐；）