[R] Question about time series

[Dennis Fisher]

I have data in the following format:

 > DATE
[1] "01/13/2004"

In order to find the difference between two data points, I presently 
use brute force to calculate the day of the year:

 > strptime(DATE, format="%m/%d/%Y")$yday
[1] 12

Although this works, it may not be robust over different years.  I 
assume that R is sufficiently clever that a much simpler approach 
exists, e.g., can I calculate the number of days since some fixed time? 
  Unfortunately, the man pages and FAQ did not lead me to an obvious 
solution.

Any help appreciated.

Dennis

Dennis Fisher MD
P < (The "P Less Than" Company)
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