R help - Nov 2007 - its does not recognize POSIXct w/ both time and Date?

Hello all,

I'm getting much further with my time-series work, but still getting 
into some problems.

I'm using POSIXct time format with both date and time.

I'd like to use that in an its object but It seems its only processes 
the date part of the POSIX time stamps:

BMU_its_data <-  its(data[BMUindex,2-4],dates=data[BMUindex,1])
Error in `row.names<-.data.frame`(`*tmp*`, value = c("2007-10-31", 
"2007-10-31",  :


The first column of the data is certainly correct, with both date and time:

 > summary(data[BMUindex,1])
                     Min.                   1st Qu.                    
Median
"2007-10-31 07:00:00 UTC" "2007-11-01 07:00:00 UTC"
"2007-11-03 07:00:00
UTC"
                     Mean                   3rd Qu.                      
Max.
"2007-11-02 21:44:12 UTC" "2007-11-04 07:00:00 UTC"
"2007-11-05 08:00:00
UTC"

Perhaps the functions used in its are unable to see the time field. I 
noticed that using unique() on the same data gives me only 6 different 
values, one for each day, with the times ignored.

Is there any time format I can use in R (through its or zoo or fCalendar 
or anything) that allows me to use tools such as unique() and so on and 
have the times (not only dates) considered?

I've chosen its because it seems to have pretty good ts specific 
plotting stuff in there, but I'd be willing to use anything that allows 
me to work with my POSIX dates down to the second. (or even msec)

Thanks.
B. Bogart

can you please give an example that I can cut from your email and run on
my machine?
 
> -----Original Message-----
> From: r-help-bounces at r-project.org 
> [mailto:r-help-bounces at r-project.org] On Behalf Of B. Bogart
> Sent: Monday, November 05, 2007 3:51 PM
> To: r-help at r-project.org
> Subject: [R] its does not recognize POSIXct w/ both time and Date?
> 
> Hello all,
> 
> I'm getting much further with my time-series work, but still 
> getting into some problems.
> 
> I'm using POSIXct time format with both date and time.
> 
> I'd like to use that in an its object but It seems its only 
> processes the date part of the POSIX time stamps:
> 
> BMU_its_data <-  its(data[BMUindex,2-4],dates=data[BMUindex,1])
> Error in `row.names<-.data.frame`(`*tmp*`, value = 
> c("2007-10-31", "2007-10-31",  :
> 
> 
> The first column of the data is certainly correct, with both 
> date and time:
> 
>  > summary(data[BMUindex,1])
>                      Min.                   1st Qu.           
>          
> Median
> "2007-10-31 07:00:00 UTC" "2007-11-01 07:00:00 UTC" 
> "2007-11-03 07:00:00 
> UTC"
>                      Mean                   3rd Qu.           
>            
> Max.
> "2007-11-02 21:44:12 UTC" "2007-11-04 07:00:00 UTC" 
> "2007-11-05 08:00:00 
> UTC"
> 
> Perhaps the functions used in its are unable to see the time field. I 
> noticed that using unique() on the same data gives me only 6 
> different 
> values, one for each day, with the times ignored.
> 
> Is there any time format I can use in R (through its or zoo 
> or fCalendar 
> or anything) that allows me to use tools such as unique() and 
> so on and 
> have the times (not only dates) considered?
> 
> I've chosen its because it seems to have pretty good ts specific 
> plotting stuff in there, but I'd be willing to use anything 
> that allows 
> me to work with my POSIX dates down to the second. (or even msec)
> 
> Thanks.
> B. Bogart
> 
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide 
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
> 



This e-mail message is intended only for the named recipient(s) above. It may
contain confidential information. If you are not the intended recipient you are
hereby notified that any dissemination, distribution or copying of this e-mail
and any attachment(s) is strictly prohibited. If you have received this e-mail
in error, please immediately notify the sender by replying to this e-mail and
delete the message and any attachment(s) from your system. Thank you.

On Nov 5, 2007 3:50 PM, B. Bogart <bbogart at sfu.ca>
wrote:
> Hello all,
>
> I'm getting much further with my time-series work, but still getting
> into some problems.
>
> I'm using POSIXct time format with both date and time.
>
> I'd like to use that in an its object but It seems its only processes
> the date part of the POSIX time stamps:
>
> BMU_its_data <-  its(data[BMUindex,2-4],dates=data[BMUindex,1])
> Error in `row.names<-.data.frame`(`*tmp*`, value =
c("2007-10-31",
> "2007-10-31",  :
>
>
> The first column of the data is certainly correct, with both date and time:
>
>  > summary(data[BMUindex,1])
>                     Min.                   1st Qu.
> Median
> "2007-10-31 07:00:00 UTC" "2007-11-01 07:00:00 UTC"
"2007-11-03 07:00:00
> UTC"
>                     Mean                   3rd Qu.
> Max.
> "2007-11-02 21:44:12 UTC" "2007-11-04 07:00:00 UTC"
"2007-11-05 08:00:00
> UTC"
>
> Perhaps the functions used in its are unable to see the time field. I
> noticed that using unique() on the same data gives me only 6 different
> values, one for each day, with the times ignored.
>
> Is there any time format I can use in R (through its or zoo or fCalendar
> or anything) that allows me to use tools such as unique() and so on and
> have the times (not only dates) considered?
>
> I've chosen its because it seems to have pretty good ts specific
> plotting stuff in there, but I'd be willing to use anything that allows
> me to work with my POSIX dates down to the second. (or even msec)
>
Please provide reproducible examples as asked in last line on every
message to r-help.

Its unlikely that 'its' ignores date fields but perhaps this will get
you going.
Each of these gives the first value and its time for each value that occurs
in the series:
> # its
> library(its)
> ii <- its(rep(1:2, 5), Sys.time() + 1:10)
> ii[!duplicated(ii)]
An object of class "its"
         1
20071105 1
20071105 2
Slot "dates":
[1] "2007-11-05 16:03:09 Eastern Standard Time"
[2] "2007-11-05 16:03:10 Eastern Standard Time"
> # zoo
> library(zoo)
> z <- zoo(rep(1:2, 5), Sys.time() + 1:10)
> z[!duplicated(z)]
2007-11-05 16:03:10 2007-11-05 16:03:11
                  1                   2