Question

我在数据框中有一个包含多个值的列

           fruits
  1   apple,banana
  2 banana,peaches
  3        peaches
  4          mango

有没有办法为水果创建一个独特价值字典将创建一个具有值的新列水果：

 fruits = apple,banana,peaches,mango

更新：我需要将值作为列而不是仅包含唯一值的列表。这样我就可以创建一个具有以下内容的最终数据框：

          fruits      fruit_apple  fruit_banana  fruit_mango  fruit_peacheas 
 1   apple,banana          1            0             0             0
 2   banana,peaches        0            1             0             1
 3   peaches               0            0             0             1
 4   mango                 0            0             1             0

Answer 1

我们可以使用cSplit_e

中的splitstackshape轻松完成此操作

library(splitstackshape)
cSplit_e(df1, "fruits", ",", type = "character", fill = 0)
#          fruits fruits_apple fruits_banana fruits_mango fruits_peaches
#1   apple,banana            1             1            0              0
#2 banana,peaches            0             1            0              1
#3        peaches            0             0            0              1
#4          mango            0             0            1              0

数据

df1 <- structure(list(fruits = c("apple,banana", "banana,peaches", "peaches", 
"mango")), .Names = "fruits", class = "data.frame", row.names = c("1", 
"2", "3", "4"))

Answer 2

您是否希望新列重复连接列表？对不起，它不是特别清楚。假设情况如此，并且您的data.frame由字符串组成而不是因素;

df <- read.delim(
text="fruits
apple,banana
banana,peaches
peaches
mango", 
sep="\n", 
header=TRUE,
stringsAsFactors=FALSE)
df
#>           fruits
#> 1   apple,banana
#> 2 banana,peaches
#> 3        peaches
#> 4          mango

df$uniquefruits <- paste0(unique(unlist(strsplit(df$fruits, split=","))), collapse=",")
df
#>           fruits               uniquefruits
#> 1   apple,banana apple,banana,peaches,mango
#> 2 banana,peaches apple,banana,peaches,mango
#> 3        peaches apple,banana,peaches,mango
#> 4          mango apple,banana,peaches,mango

或者您的意思是仅从第一个fruits列中获取其他地方未重复的值？

更新：根据评论，我认为这就是你所追求的：

uniquefruits <- unique(unlist(strsplit(df$fruits, split=",")))
uniquefruits
#> [1] "apple"   "banana"  "peaches" "mango"

df2 <- cbind(df, 
             sapply(uniquefruits, 
                    function(y) apply(df, 1, 
                                      function(x) as.integer(y %in% unlist(strsplit(x, split=","))))))
df2
#>           fruits apple banana peaches mango
#> 1   apple,banana     1      1       0     0
#> 2 banana,peaches     0      1       1     0
#> 3        peaches     0      0       1     0
#> 4          mango     0      0       0     1

理论上，您可以使用dplyr执行此操作，但我无法弄清楚如何自动执行rowwise mutate的列处理（任何人都知道如何？）< / p>

library(dplyr)
df %>% rowwise() %>% mutate(apple    = as.integer("apple"   %in% unlist(strsplit(fruits, ","))),
                            banana   = as.integer("banana"  %in% unlist(strsplit(fruits, ","))),
                            peaches  = as.integer("peaches" %in% unlist(strsplit(fruits, ","))),
                            mango    = as.integer("mango"   %in% unlist(strsplit(fruits, ","))))
#> Source: local data frame [4 x 5]
#> Groups: <by row>
#> 
#> # A tibble: 4 x 5
#>           fruits apple banana  peaches mango
#>            <chr> <int>  <int>    <int> <int>
#> 1   apple,banana     1      1        0     0
#> 2 banana,peaches     0      1        1     0
#> 3        peaches     0      0        1     0
#> 4          mango     0      0        0     1

Answer 3

以基数R：

fruits <- sort(unique(unlist(strsplit(as.character(df$fruits), split=','))))
cols <- as.data.frame(matrix(rep(0, nrow(df)*length(fruits)), ncol=length(fruits)))
names(cols) <- fruits
df <- cbind.data.frame(df, cols)
df <- as.data.frame(t(apply(df, 1, function(x){fruits <- strsplit(x['fruits'], split=','); x[unlist(fruits)] <- 1;x})))

df
          fruits apple banana mango peaches
1   apple,banana     1      1     0       0
2 banana,peaches     0      1     0       1
3        peaches     0      0     0       1
4          mango     0      0     1       0

Answer 4

您可以使用以下步骤

1）使用strsplit函数以逗号分割数据帧。

2）将向量的拆分列表拆分为单个向量。

3）然后选择list.fruits字符向量的唯一。

以下是解决方案

# DataFrame of fruits
f <- c("apple,banana","banana,peaches","peaches","mango")
fruits <- as.data.frame(f)
# fruits dataframe
               f
#1   apple,banana
#2 banana,peaches
#3        peaches
#4          mango
list.fruits <- unlist(strsplit(f,split=","))
unique.fruits <- unique(list.fruits)



# Result 
 unique.fruits
[1] "apple"   "banana"  "peaches" "mango"

R如何创建唯一值的字典

4 个答案:

数据