2017-01-30 94 views
-1

来港与数据帧df1像下面R数据帧 - 包含在聚合

+-----------------------------------------+ 
|reg |make |model |year|abs |gears|fm| 
+-----------------------------------------+ 
|ax1234|Toyota|Corolla|1999|true |6 |0 | 
|ax1235|Toyota|Corolla|1999|false|5 |0 | 
|ax1236|Toyota|Corolla|1992|false|4 |NA| 
|ax1237|Toyota|Camry |2001|true |7 |1 | 
|ax1238|Honda |Civic |1994|true |5 |NA| 
|ax1239|Honda |Civic |2000|false|6 |0 | 
|ax1240|Honda |Accord |1992|false|4 |NA| 
|ax1241|Nissan|Sunny |2001|true |6 |0 | 
|ax1242|  |  |1998|false|6 |0 | 
|ax1243|NA |NA  |1992|false|4 |NA| 
+-----------------------------------------+ 

在聚集像下面,我想NA保留make秒 - 如何实现这一目标?将makeNA组合在一起很好。

> aggregate(reg ~ make, df1, length) 
    make reg 
1   1 
2 Honda 3 
3 Nissan 1 
4 Toyota 4 
+1

'骨料(REG-addNA(做),DF1,长度)'从复制。对我来说,它的工作。 – jogo

回答

2

我们可以用dplyr和它给NA计数以及

library(dplyr) 
df1 %>% 
    group_by(make) %>% 
    summarise(reg = n())