我的for循环有什么问题-gsub行名

我想迭代所有行并重命名它们。基本上，我只想删除数据帧中的一些单词（每个行名称中都有相同的模式）

代码：

for（行名中的i（df））{
row.names（df）[i]您的顺序不好：

这里，行名中的i（df）依次是您的每个行名：

for (i in rownames(mtcars)) {
+   print(i)
+ }
[1] "Mazda RX4"
[1] "Mazda RX4 Wag"
[1] "Datsun 710"
...

所以
row.names（df）[i]
正在尝试执行
row.names（df）[“yourrowname”]
即：
row.names（mtcars）[“Mazda RX4”]
返回NA

您编写代码的方式，
i
必须是一个数字。因此：

for (i in seq_along(rownames(df))) {
  print(i)
}
[1] 1
[1] 2
[1] 3
[1] 4
[1] 5
[1] 6
[1] 7
... 

现在，要替换行名称，需要将i括起来。以下是mtcars的示例：

data("mtcars")
rownames(mtcars)
[1] "Mazda RX4"           "Mazda RX4 Wag"      
[3] "Datsun 710"          "Hornet 4 Drive"     
[5] "Hornet Sportabout"   "Valiant"            
[7] "Duster 360"          "Merc 240D"          
[9] "Merc 230"            "Merc 280"           
[11] "Merc 280C"           "Merc 450SE"         
[13] "Merc 450SL"          "Merc 450SLC"        
[15] "Cadillac Fleetwood"  "Lincoln Continental"

for (i in seq_along(rownames(mtcars))) {

  row.names(mtcars)[[i]] <- gsub(" ", "_", row.names(mtcars)[[i]])
}
rownames(mtcars)

[1] "Mazda_RX4"           "Mazda_RX4_Wag"      
[3] "Datsun_710"          "Hornet_4_Drive"     
[5] "Hornet_Sportabout"   "Valiant"            
[7] "Duster_360"          "Merc_240D"          
[9] "Merc_230"            "Merc_280"           
[11] "Merc_280C"           "Merc_450SE"         
[13] "Merc_450SL"          "Merc_450SLC" 

数据（“mtcars”）
行名（mtcars）
[1] “马自达RX4”“马自达RX4 Wag”
[3] “Datsun 710”“大黄蜂4路”
[5] “大黄蜂”关于“勇敢”
[7] “喷粉机360”“美塞240D”
[9] “Merc 230”“Merc 280”
[11] “Merc 280C”“Merc 450SE”
[13] “Merc 450SL”“Merc 450SLC”
[15] “卡迪拉克弗利特伍德”“林肯大陆”
对于（沿（行名称（mtcars））的序列中的i）{
row.names（mtcars）[[i]]不需要循环。请尝试
gsub（粘贴（words_to_remove，collapse='|'），''，rownames（df））
如果只需要删除由单词字符组成的子字符串，更安全的方法是使用
rownames（df）
data("mtcars")
rownames(mtcars)
[1] "Mazda RX4"           "Mazda RX4 Wag"      
[3] "Datsun 710"          "Hornet 4 Drive"     
[5] "Hornet Sportabout"   "Valiant"            
[7] "Duster 360"          "Merc 240D"          
[9] "Merc 230"            "Merc 280"           
[11] "Merc 280C"           "Merc 450SE"         
[13] "Merc 450SL"          "Merc 450SLC"        
[15] "Cadillac Fleetwood"  "Lincoln Continental"

for (i in seq_along(rownames(mtcars))) {

  row.names(mtcars)[[i]] <- gsub(" ", "_", row.names(mtcars)[[i]])
}
rownames(mtcars)

[1] "Mazda_RX4"           "Mazda_RX4_Wag"      
[3] "Datsun_710"          "Hornet_4_Drive"     
[5] "Hornet_Sportabout"   "Valiant"            
[7] "Duster_360"          "Merc_240D"          
[9] "Merc_230"            "Merc_280"           
[11] "Merc_280C"           "Merc_450SE"         
[13] "Merc_450SL"          "Merc_450SLC" 

rownames(mtcars) <- gsub(" ", "_", row.names(mtcars))
rownames(mtcars)
[1] "Mazda_RX4"           "Mazda_RX4_Wag"      
[3] "Datsun_710"          "Hornet_4_Drive"     
[5] "Hornet_Sportabout"   "Valiant"            
[7] "Duster_360"          "Merc_240D"          
[9] "Merc_230"            "Merc_280"           
[11] "Merc_280C"           "Merc_450SE"         
[13] "Merc_450SL"          "Merc_450SLC"