I have a dataframe with unique values $Number identifying specific points where a polygon is intersecting. Some points (i.e. 56) have 3 polygons that intersect. I want to extract the three rows which start with 56. 

```
    df <- cbind(Number = rownames(check), check)
    df

```

[df table](http://i.stack.imgur.com/M3qiY.jpg)

The issue going forward is I will be applying this for 10,000 points and won't know the repeating number such as "56". So is there a way to have a general expression which chooses rows with a general match without knowing that value?