R help - Mar 2014 - how to count dates in R

Hi,

If you want to know how many unique dates are in the dataset

`dat`: dataset
?length(unique(dat$`trade date`)) 
#[1] 6


To find the frequency of each date:
?table
?table(dat$`trade date`)
A.K.



Hi, some of you knows how to count dates in R ? 
i want to know how many dates in my data? 
my data like this 

trade date 
2014-1-16 
2014-1-16 
2013-5-25 
2014-1-13 
2014-1-10 
2013-5-14 
2013-5-24 



thanks,Pan