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space time variogram

3 messages · Jonesmus Wambua, Hodgess, Erin, Edzer Pebesma

#
hi,
am specifying a variogram with 53 years by generating the time variable as
follows:

time <- as.POSIXct(paste0(1960:2012,"-01-01"), tz = "GMT")

When i generate the map variagram, it comes with time in thousands (see
attached map). how can i make sure that it gives time in years with a
reasonable range?
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#
Erin, there is AFAIK in R no other way to represent a year then by its 
first Date, and that is what Jonesmus did.

Jonesmus, I didn't see the map that you mentioned in your email.

In the plot that you sent, lag1 refers to the first temporal lag.

variogramST will assume time to be strictly regular regardless whether 
it is -- often it isn't (years, months, even days in local time zones 
have irregular length) but nearly is. In your plot, lag1 means time[1] 
to time[2], time[2] to time[3] etc, indicating one year to the next 
(whether this is 365 days, or 366).

Please, in postings, give a complete record of what you did to obtain 
certain results -- this post might be complete speculative and hence 
completely useless to you.
On 02/26/2013 12:43 PM, Hodgess, Erin wrote: