[R] Regular time series with irregular start and end dates

[Wesley Roberts]

Dear R users,

I have a quick question regarding creating an index for a zoo object. I am using R 2.12 on winxp.

I have read through the R archives searching for information on dates and time series analysis and nothing seems to cover my question.

I am extracting data from a time series of remote sensing data. The frequency of the data is 16 days which means I cant use ts (ts likes months single days etc) and have thus been trying to replicate the following dates using ISOdatetime. 

09/13/2005 09/29/2005 10/15/2005 10/31/2005 11/16/2005 12/02/2005 12/18/2005 

So far, the only method I have found to be successful is the following

a<-ISOdatetime(2005, 9, c(13,29), 0, 0, 0)
b<-ISOdatetime(2005, 10, c(15,31), 0, 0, 0)
c<-ISOdatetime(2005, 11, c(16), 0, 0, 0)
d<-ISOdatetime(2005, 12, c(2,18), 0, 0, 0)

e<-c(a,b,c,d)
> sort(e)
[1] "2005-09-13 SAST" "2005-09-29 SAST" "2005-10-15 SAST" "2005-10-31 SAST"
[5] "2005-11-16 SAST" "2005-12-02 SAST" "2005-12-18 SAST"

This is obviously highly convoluted and is not an appropriate solution. 

I would appreciate some advice as to how I would go about creating an index that starts at date 2005-09-13 and creates the next date 16 days ahead till the finishing date 2006-10-15. Also, given the nature of my time series would I be able to use ts instead of zoo?

Many thanks for your input,
Wesley





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