daylight

I would start with the data. My source for this is the US Navy 
Sunrise/Sunset tables:
    http://aa.usno.navy.mil/data/docs/RS_OneYear.php

The page is produces is pure text; I've previously extracted the values 
with a simple Perl script, but would do it today using R (in general, 
most of the parsing I used to perform in Perl can readily be performed 
in R).

Once I had the data available as a data frame, I'd convert the columns 
to POSIXct format and then use difftime().

Cheers,
Mark

hi there,
does anyone know how to calculate the amount of daylight on every day of the
year in R? I mean the time between sunrise and sunset.

thanks



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