Question

我试图将包含字符串的行绑定到不起作用的数据帧。代码：

df1 = data.frame(id=1:5, name=c("peter","kate","lisa","daniel","paul"))
df2 = data.frame(id=5:1, age=c(11,24,25,67,2))
df3 = merge(df1,df2)
df3 = rbind(df3, c(6, "hannah", 30))
df3
str(df3)

结果：

> df1 = data.frame(id=1:5, name=c("peter","kate","lisa","daniel","paul"))
> df2 = data.frame(id=5:1, age=c(11,24,25,67,2))
> df3 = merge(df1,df2)
> df3 = rbind(df3, c(6, "hannah", 30))
Warning message:
In `[<-.factor`(`*tmp*`, ri, value = "hannah") :
  ungültiges Faktorniveau, NA erzeugt
> df3
  id   name age
1  1  peter   2
2  2   kate  67
3  3   lisa  25
4  4 daniel  24
5  5   paul  11
6  6   <NA>  30
> 
> str(df3)
'data.frame':   6 obs. of  3 variables:
 $ id  : chr  "1" "2" "3" "4" ...
 $ name: Factor w/ 5 levels "daniel","kate",..: 5 2 3 1 4 NA
 $ age : chr  "2" "67" "25" "24" ...

我看起来R使名称列成为因子列，这就是为什么它不接受字符串值。我该如何解决这个问题？哪个更合适：将整列转换为字符串列（如果存在）或将新字符串转换为因子？怎么做？

谢谢！

Answer 1

一个好的解决方案是使用dplyr包并创建tibbles而不是数据帧（tibble是一种现代类型的数据框，它将字符变量创建为标准而非因素）。

library(dplyr)
df1 <- tibble(id=1:5, name=c("peter","kate","lisa","daniel","paul"))
df2 <- tibble(id=5:1, age=c(11,24,25,67,2))
df3 <- left_join(df1,df2) #or merge(df1, df2) as you prefere so
df3 <- rbind(df3, c(6, "hannah", 30))
df3
str(df3)

R：rbind字符串到因子列

1 个答案: