R help - Jan 2011 - XTS : merge.xts seems to have problem with character vectors

Hi,

Please can you tell me what I am doing wrong.  When trying to merge two xts
objects, one of which has multiple character vectors for columns...I am just
getting NAs.
> str(t)
 POSIXct[1:1], format: "2011-01-04 11:45:37"
> y2 = xts(matrix(c(letters[1:10]),5), order.by=as.POSIXct(c(t + 1:5)))
> names(y2) = c(1,2)
> y2
                    1   2  
2011-01-04 11:45:38 "a" "f"
2011-01-04 11:45:39 "b" "g"
2011-01-04 11:45:40 "c" "h"
2011-01-04 11:45:41 "d" "i"
2011-01-04 11:45:42 "e" "j"
> y1 = xts(c(1:5), order.by=as.POSIXct(c(t + 1:5)))
> y1
                    [,1]
2011-01-04 11:45:38    1
2011-01-04 11:45:39    2
2011-01-04 11:45:40    3
2011-01-04 11:45:41    4
2011-01-04 11:45:42    5
> merge(y1, y2)
                    y1 X1 X2
2011-01-04 11:45:38  1 NA NA
2011-01-04 11:45:39  2 NA NA
2011-01-04 11:45:40  3 NA NA
2011-01-04 11:45:41  4 NA NA
2011-01-04 11:45:42  5 NA NA

Warning message:
In merge.xts(y1, y2) : NAs introduced by coercion

Why do I lose the character columns ?

Cheers,
Chris
-- 
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Sent from the R help mailing list archive at Nabble.com.

On Tue, Jan 4, 2011 at 12:42 PM, rivercode <aquanyc at gmail.com>
wrote:
>
> Hi,
>
> Please can you tell me what I am doing wrong. ?When trying to merge two xts
> objects, one of which has multiple character vectors for columns...I am
just
> getting NAs.
>
>> str(t)
> ?POSIXct[1:1], format: "2011-01-04 11:45:37"
>
>> y2 = xts(matrix(c(letters[1:10]),5), order.by=as.POSIXct(c(t + 1:5)))
>> names(y2) = c(1,2)
>> y2
> ? ? ? ? ? ? ? ? ? ?1 ? 2
> 2011-01-04 11:45:38 "a" "f"
> 2011-01-04 11:45:39 "b" "g"
> 2011-01-04 11:45:40 "c" "h"
> 2011-01-04 11:45:41 "d" "i"
> 2011-01-04 11:45:42 "e" "j"
>
>> y1 = xts(c(1:5), order.by=as.POSIXct(c(t + 1:5)))
>> y1
> ? ? ? ? ? ? ? ? ? ?[,1]
> 2011-01-04 11:45:38 ? ?1
> 2011-01-04 11:45:39 ? ?2
> 2011-01-04 11:45:40 ? ?3
> 2011-01-04 11:45:41 ? ?4
> 2011-01-04 11:45:42 ? ?5
>
>> merge(y1, y2)
> ? ? ? ? ? ? ? ? ? ?y1 X1 X2
> 2011-01-04 11:45:38 ?1 NA NA
> 2011-01-04 11:45:39 ?2 NA NA
> 2011-01-04 11:45:40 ?3 NA NA
> 2011-01-04 11:45:41 ?4 NA NA
> 2011-01-04 11:45:42 ?5 NA NA
>
> Warning message:
> In merge.xts(y1, y2) : NAs introduced by coercion
>
> Why do I lose the character columns ?
>
Because zoo / xts objects are matrices with an ordered index (a time
index in the case of xts).  You can't mix types in a matrix.

--
Joshua Ulrich  |  FOSS Trading: www.fosstrading.com

> Cheers,
> Chris
> --
> View this message in context:
http://r.789695.n4.nabble.com/XTS-merge-xts-seems-to-have-problem-with-character-vectors-tp3174125p3174125.html
> Sent from the R help mailing list archive at Nabble.com.
>
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