R语言 subset()函数用法

subset() 函数：

subset(dataset , subset , select )

dataset 是 要进行操作的数据集

subset 是对数据的某些字段进行操作

select 选取要显示的字段

Example : 

```{r spdep}
hightech
aa = subset(hightech,year==2001&province=="北京",select = c("year","province","PAT"))
bb = subset(hightech,year==2001|province=="北京",select = c("year","province","NPO"))
aa
bb
```

 aa:

 bb: