我需要通过眼睛颜色反向按字母顺序排序，breaking ties by increasing weight并找出谁是上面的第四个男性！ aggregate是否具有sort功能？ R中的break the ties by increasing weight是什么意思？你能举个例子来答案吗？
这是数据框：
jalal
age sex weight eye.color hair.color
1 23 F 93.8 blue black
2 21 M 180.8 amber gray
3 22 F 196.5 hazel gray
4 22 M 256.2 amber black
5 21 M 219.6 blue gray
6 16 F 152.1 blue gray
7 21 F 183.3 gray chestnut
8 18 M 179.1 brown blond
9 15 M 206.1 blue white
10 19 M 211.6 brown blond
11 20 F 209.4 blue white
12 21 M 194.0 brown auburn
13 22 F 204.1 green black
14 21 F 157.4 hazel red
15 15 F 238.0 green gray
16 20 F 154.8 gray gray
17 16 F 245.8 gray gray
18 23 M 198.2 gray red
19 19 M 169.1 green brown
20 24 M 198.0 green gray
答案 0 :(得分：2)
dat <- read.table(header = TRUE, text = "nr age sex weight eye.color hair.color
1 23 F 93.8 blue black
2 21 M 180.8 amber gray
3 22 F 196.5 hazel gray
4 22 M 256.2 amber black
5 21 M 219.6 blue gray
6 16 F 152.1 blue gray
7 21 F 183.3 gray chestnut
8 18 M 179.1 brown blond
9 15 M 206.1 blue white
10 19 M 211.6 brown blond
11 20 F 209.4 blue white
12 21 M 194.0 brown auburn
13 22 F 204.1 green black
14 21 F 157.4 hazel red
15 15 F 238.0 green gray
16 20 F 154.8 gray gray
17 16 F 245.8 gray gray
18 23 M 198.2 gray red
19 19 M 169.1 green brown
20 24 M 198.0 green gray")
require(dplyr)
ndat <- dat %.%
arrange(desc(eye.color), desc(weight)) %.%
filter(sex == 'M')
ndat[4,]
nr age sex weight eye.color hair.color
4 10 19 M 211.6 brown blond
答案 1 :(得分：2)
使用xtfrm函数对<{3}}进行小修改 -
sorted.jalal <- jalal[with(jalal, order(-xtfrm(eye.color), weight)), ]
sorted.jalal[sorted.jalal$sex == "M", ][4,]
age sex weight eye.color hair.color
8 18 M 179.1 brown blond
答案 2 :(得分：1)
有几乎肯定比这更简单的方法，但我认为这是有效的。我不得不两次使用order才能让它发挥作用。
jalal <- read.table(text = '
age sex weight eye.color hair.color
23 F 93.8 blue black
21 M 180.8 amber gray
22 F 196.5 hazel gray
22 M 256.2 amber black
21 M 219.6 blue gray
16 F 152.1 blue gray
21 F 183.3 gray chestnut
18 M 179.1 brown blond
15 M 206.1 blue white
19 M 211.6 brown blond
20 F 209.4 blue white
21 M 194.0 brown auburn
22 F 204.1 green black
21 F 157.4 hazel red
15 F 238.0 green gray
20 F 154.8 gray gray
16 F 245.8 gray gray
23 M 198.2 gray red
19 M 169.1 green brown
24 M 198.0 green gray
', header = TRUE, stringsAsFactors = FALSE)
jalal2 <- jalal[order(jalal$eye.color, -jalal$weight),] # order data frame
jalal3 <- jalal2[order(-1:-nrow(jalal2)),] # reverse order data frame
jalal3
jalal4 <- jalal3[jalal3$sex == 'M',] # select males
jalal4[4,] # select fourth male
age sex weight eye.color hair.color
8 18 M 179.1 brown blond
如果你想把重量排在另一个方向，我认为这样做：
jalal2 <- jalal[order(jalal$eye.color, jalal$weight),] # order data frame
jalal3 <- jalal2[order(-1:-nrow(jalal2)),] # reverse order data frame
jalal3
jalal4 <- jalal3[jalal3$sex == 'M',] # select males
jalal4[4,] # select fourth male
age sex weight eye.color hair.color
10 19 M 211.6 brown blond
答案 3 :(得分：0)
> sorted.jalal <- jalal[with(jalal, order(eye.color, -weight, decreasing=TRUE)), ]
> sorted.jalal
age sex weight eye.color hair.color count
8 21 F 131.7 hazel brown 1
12 22 M 180.4 hazel chestnut 1
14 27 M 208.5 hazel gray 1
5 20 F 142.7 green chestnut 1
13 20 F 185.9 green auburn 1
16 20 F 195.7 green auburn 1
17 22 M 199.1 green red 1
7 23 M 276.3 green black 1
1 22 F 149.7 gray blond 1
3 22 F 166.5 gray white 1
11 23 F 176.2 gray gray 1
18 19 F 199.5 gray chestnut 1
10 23 M 214.1 gray chestnut 1
20 18 M 143.9 brown chestnut 1
6 22 M 133.7 blue black 1
4 21 F 179.8 blue white 1
9 17 M 194.8 blue brown 1
19 15 M 267.1 blue brown 1
15 20 F 187.1 amber white 1
2 19 M 250.2 amber white 1