四分位数按组数据帧

Question

我有一个看起来像这样的数据保存为新的变量：

id <- c(1,1,1,2,2,2,3,3,3,4,4,4,5,5,5,6,6,6,7,7,7,8,8,8,9,9,9) 
yr <- c(1,2,3,1,2,3,1,2,3,1,2,3,1,2,3,1,2,3,1,2,3,1,2,3,1,2,3) 
gr <- c(3,4,5,3,4,5,3,4,5,4,5,6,4,5,6,4,5,6,5,6,7,5,6,7,5,6,7) 
x <- c(33,48,31,41,31,36,25,38,28,17,39,53,60,60,19,39,34,47,20,28,38,15,17,49,48,45,39) 
df <- data.frame(id,yr,gr,x) 

    id yr gr x 
1 1 1 3 33 
2 1 2 4 48 
3 1 3 5 31 
4 2 1 3 41 
5 2 2 4 31 
6 2 3 5 36 
7 3 1 3 25 
8 3 2 4 38 
9 3 3 5 28 
10 4 1 4 17 
11 4 2 5 39 
12 4 3 6 53 
13 5 1 4 60 
14 5 2 5 60 
15 5 3 6 19 
16 6 1 4 39 
17 6 2 5 34 
18 6 3 6 47 
19 7 1 5 20 
20 7 2 6 28 
21 7 3 7 38 
22 8 1 5 15 
23 8 2 6 17 
24 8 3 7 49 
25 9 1 5 48 
26 9 2 6 45 
27 9 3 7 39 

我想创建一个包含计算的“X”的位数的数据帧的新变量在“年”和“gr”的每个独特组合中。也就是说，我不想根据示例中的所有27行数据找到“x”的分位数，我想通过两个分组变量计算分位数：yr和gr。例如，当yr = 1和gr = 3，yr = 1和gr = 4等时，“x”的分位数等。

一旦计算出这些值，我希望它们被附加到数据框中一列，说“x_quant”。

我能够将数据拆分成我需要的单独组，并且我知道如何计算分位数，但是我无法以适合于在现有中创建新列的方式组合这两个步骤数据帧。

你们都可以提供的任何帮助将会非常令人满意！非常感谢！

〜KJ

Answer 1

# turn "yr" and "gr" into sortable column 
df$y <- paste(df$yr,"",df$gr) 
df.ordered <- df[order(df$y),] #sort df based on group 
grp <- split(df.ordered,df.ordered$y);grp 

# get quantiles and turn results into string 
q <- vector('list') 
for (i in 1:length(grp)) { 
    a <- quantile(grp[[i]]$x) 
    q[i] <- paste(a[1],"",a[2],"",a[3],"",a[4],"",a[5]) 
} 
x_quant <- unlist(sapply(q, `[`, 1)) 
x_quant <- rep(x_quant,each=3) 

# append quantile back to data frame. Gave new column a more descriptive name 
df.ordered$xq_0_25_50_75_100 <- x_quant 
df.ordered$y <- NULL 
df <- df.ordered;df </pre> 

输出：

> # turn "yr" and "gr" into sortable column 
> df$y <- paste(df$yr,"",df$gr) 
> df.ordered <- df[order(df$y),] #sort df based on group 
> grp <- split(df.ordered,df.ordered$y);grp 
$`1 3` 
    id yr gr x y 
1 1 1 3 33 1 3 
4 2 1 3 41 1 3 
7 3 1 3 25 1 3 

$`1 4` 
    id yr gr x y 
10 4 1 4 17 1 4 
13 5 1 4 60 1 4 
16 6 1 4 39 1 4 

$`1 5` 
    id yr gr x y 
19 7 1 5 20 1 5 
22 8 1 5 15 1 5 
25 9 1 5 48 1 5 

$`2 4` 
    id yr gr x y 
2 1 2 4 48 2 4 
5 2 2 4 31 2 4 
8 3 2 4 38 2 4 

$`2 5` 
    id yr gr x y 
11 4 2 5 39 2 5 
14 5 2 5 60 2 5 
17 6 2 5 34 2 5 

$`2 6` 
    id yr gr x y 
20 7 2 6 28 2 6 
23 8 2 6 17 2 6 
26 9 2 6 45 2 6 

$`3 5` 
    id yr gr x y 
3 1 3 5 31 3 5 
6 2 3 5 36 3 5 
9 3 3 5 28 3 5 

$`3 6` 
    id yr gr x y 
12 4 3 6 53 3 6 
15 5 3 6 19 3 6 
18 6 3 6 47 3 6 

$`3 7` 
    id yr gr x y 
21 7 3 7 38 3 7 
24 8 3 7 49 3 7 
27 9 3 7 39 3 7 

> # get quantiles and turn results into string 
> q <- vector('list') 
> for (i in 1:length(grp)) { 
+ a <- quantile(grp[[i]]$x) 
+ q[i] <- paste(a[1],"",a[2],"",a[3],"",a[4],"",a[5]) 
+ } 
> x_quant <- unlist(sapply(q, `[`, 1)) 
> x_quant <- rep(x_quant,each=3) 
> # append quantile back to data frame 
> df.ordered$xq_0_25_50_75_100 <- x_quant 
> df.ordered$y <- NULL 
> df <- df.ordered 
> df 
    id yr gr x  xq_0_25_50_75_100 
1 1 1 3 33  25 29 33 37 41 
4 2 1 3 41  25 29 33 37 41 
7 3 1 3 25  25 29 33 37 41 
10 4 1 4 17 17 28 39 49.5 60 
13 5 1 4 60 17 28 39 49.5 60 
16 6 1 4 39 17 28 39 49.5 60 
19 7 1 5 20 15 17.5 20 34 48 
22 8 1 5 15 15 17.5 20 34 48 
25 9 1 5 48 15 17.5 20 34 48 
2 1 2 4 48 31 34.5 38 43 48 
5 2 2 4 31 31 34.5 38 43 48 
8 3 2 4 38 31 34.5 38 43 48 
11 4 2 5 39 34 36.5 39 49.5 60 
14 5 2 5 60 34 36.5 39 49.5 60 
17 6 2 5 34 34 36.5 39 49.5 60 
20 7 2 6 28 17 22.5 28 36.5 45 
23 8 2 6 17 17 22.5 28 36.5 45 
26 9 2 6 45 17 22.5 28 36.5 45 
3 1 3 5 31 28 29.5 31 33.5 36 
6 2 3 5 36 28 29.5 31 33.5 36 
9 3 3 5 28 28 29.5 31 33.5 36 
12 4 3 6 53  19 33 47 50 53 
15 5 3 6 19  19 33 47 50 53 
18 6 3 6 47  19 33 47 50 53 
21 7 3 7 38 38 38.5 39 44 49 
24 8 3 7 49 38 38.5 39 44 49 
27 9 3 7 39 38 38.5 39 44 49 
>