獨特/排序在data.frame

Question

我有這樣一個數據幀：

x=c("01","01","01","22","22","03","03","03","35","35") 
y=c("f","f","f","m","m","m","m","m","f","f") 
df=data.frame(spn=x, sex=y) 

似乎是：

spn sex 
1 01 f 
2 01 f 
3 01 f 
4 22 m 
5 22 m 
6 03 m 
7 03 m 
8 03 m 
9 35 f 
10 35 f 

我希望做的是排序的DF $ SPN和讓它只出現一次。適當的df $性別以及，如：

spn sex 
1 01 f 
2 03 m 
3 22 m 
4 35 f 

我該怎麼做？非常感謝！

Answer 1

df <- df[order(df$spn), ] 
> df[!duplicated(df), ] 
    spn sex 
1 01 f 
6 03 m 
4 22 m 
9 35 f 

Answer 2

df2 = df[!duplicated(df), ] # Remove duplicated rows. 
df3 = df2[order(df2$spn), ] # Sort by the spn column. 

df3 
# spn sex 
#1 01 f 
#6 03 m 
#4 22 m 
#9 35 f 

Answer 3

使用獨有然後順序：

df <- unique(df) 
df[order(df$spn), ]