我在R中有一个如下所示的数据框:
df <- data.frame(apple = c("apple", "apple", "applebad", "apple", "apple"),
orange = c("orangebad", "orangebad", "orange", "orange", "orange"),
pear = c("pear", "pear", "pear", "pearbad", "pear"))
然而,我想从这个数据框中将“bad”的后缀更改为“rotten”的前缀,以便获得以下数据框:
df_new <- data.frame(apple = c("apple", "apple", "rottenapple", "apple", "apple"),
orange = c("rottenorange", "rottenorange", "orange", "orange", "orange"),
pear = c("pear", "pear", "pear", "rottenpear", "pear"))
我知道可以使用str_replace(来自stringr)或gsub逐列执行此操作:
df$apple <- gsub("applebad", paste0("rottenapple"), df$apple)
df$apple <- str_replace(df$apple, "applebad", "rottenapple")
但我不确定如何做才能迭代数据框,而无需声明“rottenapple”、“rottenpear”,因为我的真实数据集有数百列。我尝试了以下方法,但并不起作用:
item <- c("apple", "orange", "pear")
df[,1] <- str_replace(df[,1], "bad", paste0("rotten", item[1]))
非常感谢任何帮助。