我想遍历我拥有的数据帧列表并重命名列名称。这是数据帧的示例,
dput(df)
df1 <- structure(list(v1..x = c("Silva", "Brandon", "Mango"),
t2.v = c("James","Jane", "Egg")),
class = "data.frame", row.names = c(NA, -3L))
dput(df2)
df2 <- structure(list(v1..x = c("Silva", "Brandon", "Mango"),
t2.r = c("James","Jane", "Egg")),
class = "data.frame", row.names = c(NA, -3L))
dput(df3)
df3 <- structure(list(v1..x = c("Silva", "Brandon", "Mango"),
t2.v = c("James","Jane", "Egg"),
d3...c = c("James","Jane", "Egg")),
class = "data.frame", row.names = c(NA, -3L))
我想遍历此数据框的列表并重命名列。我有一个要替换的列的列表,我想使用setnames以便跳过不存在的列,以防它在数据帧中找到一个。这里是我尝试过的方法,但只更改了第一列
lst_df <- list(df1,df2,df3)
oldnames<- c('v1..x','t2.v','d3...c')
newnames <- c('v1','t2_v','d3')
lst <- lapply(lst_df, function(x) setNames(x, gsub(oldnames, newnames, names(x))) )
注意某些数据框中的列长度可能不相同。请帮助
在这种情况下,data.table
可能会派上用场。其setnames
功能比setNames
更灵活。
library(data.table)
oldnames<- c('v1..x','t2.v','d3...c')
newnames <- c('v1','t2_v','d3')
# convert df-s to data.table
lapply(lst_df, setDT)
# setnames function from data.table is quite flexible
lapply(lst_df, setnames, oldnames, newnames, skip_absent = TRUE)
请注意,这只会更改完全匹配。如果要更改这些字符串模式,最简单的方法可能是运行for并使用正则表达式。