[R] How can I declare an empty zoo object?
smartpink111 at yahoo.com
Tue Jul 31 14:23:11 CEST 2012
#With indices on one
#with a different index. Here, I get warning message.
In merge.zoo(..., all = all, fill = fill, suffixes = suffixes, retclass = "zoo", :
Index vectors are of different classes: integer numeric
I am using R 2.15. Don't know if you get warnings or not.
From: jpm miao <miaojpm at gmail.com>
To: R. Michael Weylandt <michael.weylandt at gmail.com>
Cc: r-help <r-help at r-project.org>; smartpink111 at yahoo.com
Sent: Tuesday, July 31, 2012 3:40 AM
Subject: Re: [R] How can I declare an empty zoo object?
1. I try this
xzoo <- zoo()
and it does work. OK, I will read the reference you provide to find out why not to do so
2. How can I create an array of zoo objects?
3. Do you mean by "R's wisest virgil" Pat Burns' R Inferno?
Even when indices (dates) of two zoo object don't match, I can cbind them. It works for me!
2012/7/31 R. Michael Weylandt <michael.weylandt at gmail.com>
On Mon, Jul 30, 2012 at 11:18 PM, jpm miao <miaojpm at gmail.com> wrote:
>> I let xzoo be an empty object:
>This sounds like the start of a bad idea....
>> and I have an existing zoo object x1zoo_f. I would like to combine
>> the two to make a new zoo object, and continue doing so in a loop,
>> which is not shown here. However, when I type
>>> xzoo<-cbind(xzoo, x1zoo_f)
>Yep: the real answer is "don't do that." Since R is
>copy-on-write+pass-by-reference and a few other nice things, this will
>be painfully gut-wrenchingly paint-dryingly slow :-) Much better is to
>make all your "x1zoo_f" objects and cbind them at once.
>The perils of this idea and the appropriate fixings thereof have been
>discussed here there and everywhere, but I think Pat Burn's
>presentation in "the R Inferno" is the best (and certainly the most
>fun) -- it's a worthwhile read and, perhaps an even higher compliment,
>a worthwhile re-read.
>Based on my rough memories of your recent posts, you won't understand
>it all in the first pass (few do -- I certainly don't), but over time
>you'll gain immensely from the work of one of R's wisest Virgils.
>> An error message emerges
>> Error in zoo(structure(x, dim = dim(x)), index(x), ...) :
>> “x” : attempt to define invalid zoo object
>> Is there any way to define an empty zoo object?
>xzoo <- zoo()
>But like I said: don't do that.
>> [[alternative HTML version deleted]]
>> R-help at r-project.org mailing list
>> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
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