The warning message does tell you exactly what was wrong. You are
trying to merge zoo objects that have two different index classes.
The first is "POSIXct" and the second is "Date" class. Next time
please provide your data in reproducible form
as shown here:
> library(zoo)
> z1 <- zoo(1:6, as.Date(c("1950-01-05", "1950-01-06", "1950-01-09",
+ "1950-01-10", "1950-01-11", "1950-01-12")))
> z2 <- zoo(c(16.66, 16.85, 16.93, 16.98, 17.08, 17.03),
+ as.POSIXct(c("1950-01-03, GMT", "1950-01-04, GMT", "1950-01-05, GMT",
+ "1950-01-06, GMT", "1950-01-09 GMT", "1950-01-10 GMT")))
>
> merge(z1, z2 = aggregate(z2, as.Date, identity))
z1 z2
1950-01-03 NA 16.66
1950-01-04 NA 16.85
1950-01-05 1 16.93
1950-01-06 2 16.98
1950-01-09 3 17.08
1950-01-10 4 17.03
1950-01-11 5 NA
1950-01-12 6 NA
>
>
> # or
> z2.Date <- z2
> time(z2.Date) <- as.Date(time(z2.Date))
>
> merge(z1, z2.Date)
z1 z2.Date
1950-01-03 NA 16.66
1950-01-04 NA 16.85
1950-01-05 1 16.93
1950-01-06 2 16.98
1950-01-09 3 17.08
1950-01-10 4 17.03
1950-01-11 5 NA
1950-01-12 6 NA
On Thu, May 20, 2010 at 10:48 AM, Research <[email protected]> wrote:
> Hello,
>
> I have a zoo time series object (say a) with the following time
> stamp/format
>
>
>
> [1] "1950-01-03 GMT" "1950-01-04 GMT" "1950-01-05 GMT" "1950-01-06 GMT"
> [5] "1950-01-09 GMT" "1950-01-10 GMT"
>
>
> and another (say b) with
>
>
> [1] "1950-01-05" "1950-01-06" "1950-01-09" "1950-01-10" "1950-01-11"
> [6] "1950-01-12"
>
>
> I want to merge these series but when I try:
>
>
>> head(merge(a, b ))
> a b
> 1950-01-03 02:00:00 16.66 NA
> 1950-01-04 02:00:00 16.85 NA
> 1950-01-05 02:00:00 16.93 NA
> 1950-01-06 02:00:00 16.98 NA
> 1950-01-09 02:00:00 17.08 NA
> 1950-01-10 02:00:00 17.03 NA
> Warning message:
> In merge.zoo(a, b) :
> Index vectors are of different classes: POSIXt Date
>>
>
> Anybody can help? I tried as.POSIXct(a,tz="GMT") but it doesn't seem to
> work....
>
> Many thanks in advance!
>
> Costas
> _
> platform i386-pc-mingw32
> arch i386
> os mingw32
> system i386, mingw32
> status
> major 2
> minor 10.1
> year 2009
> month 12
> day 14
> svn rev 50720
> language R
> version.string R version 2.10.1 (2009-12-14)
>>
>
> ______________________________________________
> [email protected] 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.
>
______________________________________________
[email protected] 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.