a) Please read the Posting Guide and post in plain text as it says to do. This
is an adjustment you must make in your email client software, we cannot advise
you how to do it here.
b) Not clear why you want a matrix. A vector is more typical in R; most of the
time using n*1 matrices is an unnecessary Matlab habit.
c) See ?diff
diff(datetime)
or if you definitely need it:
matrix(diff(datetime),ncol=1)
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Sent from my phone. Please excuse my brevity.
Andras Farkas <motyoc...@yahoo.com> wrote:
>Dear All
>�
>I have the following code:
>�
>datetime <-c("1/1/13 00:00","1/1/13 12:00","1/2/13 00:00","1/2/13
>12:00")
>datetime <-as.POSIXct(datetime,format='%m/%d/%Y %H:%M')
>times
><-matrix(c(difftime(datetime[2],datetime[1],units="hours"),difftime(datetime[3],datetime[2],units="hours"),difftime(datetime[4],datetime[3],units="hours")))
>
>I would like to aks for some directions on how to make the 'times'
>object code a bit more "uniform" to accept differenth lenths of
>'datetime'... Occasionally I have the 'datetime' object include�up
>to�15 date and time points, but that code limits the system from
>accepting a longer 'datetime' object. This is what that looks like
>(basically same as above, but much longer):
>�
>datetime <-c("1/1/13 00:00","1/1/13 12:00","1/2/13 00:00","1/2/13
>12:00")
>datetime <-as.POSIXct(datetime,format='%m/%d/%Y %H:%M')
>times
><-matrix(c(difftime(datetime[2],datetime[1],units="hours"),difftime(datetime[3],datetime[2],units="hours"),difftime(datetime[4],datetime[3],units="hours"),difftime(datetime[5],datetime[4],units="hours"),difftime(datetime[6],datetime[5],units="hours"),difftime(datetime[7],datetime[6],units="hours"),difftime(datetime[8],datetime[7],units="hours"),difftime(datetime[9],datetime[8],units="hours"),difftime(datetime[10],datetime[9],units="hours"),difftime(datetime[11],datetime[10],units="hours"),difftime(datetime[12],datetime[11],units="hours"),difftime(datetime[13],datetime[12],units="hours"),difftime(datetime[14],datetime[13],units="hours"),difftime(datetime[15],datetime[14],units="hours"),difftime(datetime[16],datetime[15],units="hours")))
>
>appreciate the help,
>�
>Andras
> [[alternative HTML version deleted]]
>
>
>
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>
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