Missing data?
On Sun, Nov 27, 2011 at 8:10 PM, Kevin Burton <rkevinburton at charter.net> wrote:
This has been very helpful. Thank you. At the risk of further confirming my ignorance and taxing your patience I would like to add another question. How would I modify this code so that each week starts with the same day of the week regardless of the year? I would add this stipulation so that for multiple years I always get the same 'week-number' like
format(as.Date("2011-11-27"), "%W-%w")
[1] "47-0" The convention (at least for US culture) seems to be that the week starts with Sunday (it is index 0 for day of week). So it would be convenient if the code was modified so that each 'week' began on Sunday. The partial at the beginning would just start with the day of week that was at the start. I still would want to aggregate that 'week-number's that are greater than 51 like you have shown.
It would be the same except replace the calculation of yr.wk with: tt <- time(z) yr.wk <- as.numeric(format(tt, "%Y")) + pmin(as.numeric(format(tt, "%W")), 51)/52 This puts the 1st Sunday of the year and the days prior to it in week 0, the next 7 days are in week 1 and so on. All days after the 51st Sunday are either in week 51 or are forced to be.
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