R help - Sep 2011 - Seasonal and 11-day subset for zoo object

I have a zooreg object and I want to be able to generate a value for seasons
and 11-day composites paste it onto my zoo data frame, along with year,
month and days.

Right now I have the following to work from:

eg. dat.zoo.mdy <- with(month.day.year(time(dat.zoo)), cbind(dat.zoo, year,
month, day, quarter = (month - 1) %/% 3 + 1, dow
as.numeric(format(time(dat.zoo), "%w"))))

For the seasons, I have been trying to replace 'quarter' with a seasonal
value of "1" for Dec-Jan-Feb, "2" for Mar-Apr-May,
"3" for Jun-Jul-Aug, "4"
for Sep-Oct-Nov.

dat.zoo.mdy <- with(month.day.year(time(dat.zoo)), cbind(dat.zoo, year,
month, day,
season=for(i in nrow(dat.zoo.mdy)) {
         if (month[i] == 12) {
         quarter[i]=1
         } else if (month[i] == 3) {
         quarter[i]=2
         } else if (month[i] == 6) {
         quarter[i]=3
         } else quarter[i]=4 }, dow = as.numeric(format(time(dat.zoo),
"%w"))))

However, this gives me the error: "Error in zoo(structure(x, dim = dim(x)),
index(x), ...) :
  “x” : attempt to define illegal zoo object"

I'd like to get an 11-day value as well to replace the dow in the first
example, but I'm still trying to figure out if there is an easy way to do
this in zoo.

Any ideas would be greatly appreciated.

Katrina

	[[alternative HTML version deleted]]

On Wed, Sep 7, 2011 at 9:59 PM, Katrina Bennett <kebennett at alaska.edu>
wrote:
> I have a zooreg object and I want to be able to generate a value for
seasons
> and 11-day composites paste it onto my zoo data frame, along with year,
> month and days.
>
> Right now I have the following to work from:
>
> eg. dat.zoo.mdy <- with(month.day.year(time(dat.zoo)), cbind(dat.zoo,
year,
> month, day, quarter = (month - 1) %/% 3 + 1, dow >
as.numeric(format(time(dat.zoo), "%w"))))
>
> For the seasons, I have been trying to replace 'quarter' with a
seasonal
> value of "1" for Dec-Jan-Feb, "2" for Mar-Apr-May,
"3" for Jun-Jul-Aug, "4"
> for Sep-Oct-Nov.
>
> dat.zoo.mdy <- with(month.day.year(time(dat.zoo)), cbind(dat.zoo, year,
> month, day,
> season=for(i in nrow(dat.zoo.mdy)) {
> ? ? ? ? if (month[i] == 12) {
> ? ? ? ? quarter[i]=1
> ? ? ? ? } else if (month[i] == 3) {
> ? ? ? ? quarter[i]=2
> ? ? ? ? } else if (month[i] == 6) {
> ? ? ? ? quarter[i]=3
> ? ? ? ? } else quarter[i]=4 }, dow = as.numeric(format(time(dat.zoo),
> "%w"))))
>
> However, this gives me the error: "Error in zoo(structure(x, dim =
dim(x)),
> index(x), ...) :
> ??x? : attempt to define illegal zoo object"
>
> I'd like to get an 11-day value as well to replace the dow in the first
> example, but I'm still trying to figure out if there is an easy way to
do
> this in zoo.
>
dat.zoo and "11 days composite" in the question were not defined but
we can get the seasons by calculating the quarter of the following
month:
> d <- seq(as.Date("2011-01-01"), length = 12, by =
"month")
> as.numeric(format(as.yearqtr(as.yearmon(d) + 1/12), "%q"))
 [1] 1 1 2 2 2 3 3 3 4 4 4 1


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