timeDate use

["Gupta, Pankaj*" <GuptaP@cder.fda.gov>]

Dear users,

I have a question about manipulating time-date data. Specifically, I have two columns (class factor), each containing dates which constitute the levels. e.g. an entry in the columns looks like "12AUG2000". I wish to calculate the time interval by taking difference between the respective rows in the two columns. However, when I try to use "timeDate" for each of the columns (to convert to a Splus date format) it gives me an error.

I have tried using timeDate as follows:

timeDate(as.character(column),in.format="%d%b%Y",format="%2m%2d%4Y")
 
I would appreciate any help/suggestions in this regard.

Pankaj Gupta