将csv值转换为R中的表

Question

我有一些来自民意调查的数据,如下所示:

                                    Freetime_activities
1                       Travelling, On the PC, Clubbing
2                           Sports, On the PC, Clubbing
3                                              Clubbing
4                                             On the PC
5                       Travelling, On the PC, Clubbing
6                                             On the PC
7                               Watching TV, Travelling

我想得到每个值的计数(在PC上等多少次行/ PC),但是我在分割值时遇到了麻烦.R中是否有一个函数可以做例如:

split("A,B,C") -> 
1 A
2 B
3 C

或者是否有直接从列中计算值的直接解决方案？

Answer 1

我们可以用strsplit分割用分隔栏", "),unlist将list输出,然后用table获得的频率

 tbl <- table(unlist(strsplit(as.character(df1$Freetime_activities),
                                          ", ")))
 as.data.frame(tbl)
 #         Var1 Freq
 #1    Clubbing    4
 #2   On the PC    5
 #3      Sports    1
 #4  Travelling    3
 #5 Watching TV    1

注意:as.character如果列是a factor,strsplit只能使用character向量,则使用此处.

或者另一种选择是使用scan提取元素,然后table获取频率.

 table(trimws(scan(text = as.character(df1$Freetime_activities),
                   what = "", sep = ",")))

或者使用read.table与unlist和table

table(unlist(read.table(text = as.character(df1$Freetime_activities), 
           sep = ",", fill = TRUE, strip.white = TRUE)))

编辑:基于@David Arenburg的评论.

数据

df1 <- structure(list(Freetime_activities = c("Travelling, On the PC, 
  Clubbing", 
"Sports, On the PC, Clubbing", "Clubbing", "On the PC", "Travelling, 
 On the PC, Clubbing", 
"On the PC", "Watching TV, Travelling")), 
 .Names = "Freetime_activities", 
 class = "data.frame", row.names = c("1", 
"2", "3", "4", "5", "6", "7"))