我是R的新手,想要对称为“权重”的数据框进行排序。以下是详细信息:
>str(weights)
'data.frame': 57 obs. of 1 variable:
$ attr_importance: num 0.04963 0.09069 0.09819 0.00712 0.12543 ...
> names(weights)
[1] "attr_importance"
> dim(weights)
[1] 57 1
> head(weights)
attr_importance
make 0.049630556
address 0.090686474
all 0.098185517
num3d 0.007122618
our 0.125433292
over 0.075182467
我想按attr_importance的降序排序,但我也想保留相应的行名。
我试过了:
> weights[order(-weights$attr_importance),]
但它给了我一个“数字”背面。
我想要一个数据帧 - 按attr_importance排序,并且CORRESPONDING行名称保持不变。我怎么能这样做?
提前致谢。
答案 0 :(得分:9)
以下是data.frame排序的重要比较:
How to sort a dataframe by column(s)?
使用我现在首选的解决方案arrange
:
dd <- data.frame(b = factor(c("Hi", "Med", "Hi", "Low"),
levels = c("Low", "Med", "Hi"), ordered = TRUE),
x = c("A", "D", "A", "C"), y = c(8, 3, 9, 9),
z = c(1, 1, 1, 2))
library(plyr)
arrange(dd,desc(z),b)
b x y z
1 Low C 9 2
2 Med D 3 1
3 Hi A 8 1
4 Hi A 9 1
答案 1 :(得分:8)
由于您的data.frame只有一列,因此您需要设置drop=FALSE
以防止删除维度:
weights[order(-weights$attr_importance),,drop=FALSE]
# attr_importance
# our 0.125433292
# all 0.098185517
# address 0.090686474
# over 0.075182467
# make 0.049630556
# num3d 0.007122618
答案 2 :(得分:0)
rankdata.txt
regno name total maths science social cat
1 SUKUMARAN 400 78 89 73 S
2 SHYAMALA 432 65 79 87 S
3 MANOJ 500 90 129 78 C
4 MILYPAULOSE 383 59 88 65 G
5 ANSAL 278 39 77 60 O
6 HAZEENA 273 45 55 56 O
7 MANJUSHA 374 50 99 52 C
8 BILBU 408 81 97 72 S
9 JOSEPHROBIN 374 57 85 68 G
10 SHINY 381 70 79 70 S
z <- data.frame(rankdata)
z[with(z, order(-total+ maths)),] #order function maths group selection
z
z[with(z, order(name)),] # sort on name
z