[R] How to avoid conversion to factors (data frame to zoo)

[John Kane]

http://finzi.psych.upenn.edu/R/Rhelp02a/archive/98227.html

Your Rprofile has the setting
options(stringsAsFactors = TRUE)

If you override it globally  by using 

options(stringsAsFactors = FALSE) 

 it will give you what you want but observe Gabor's
caveat. I don't know of the other solution re settings
stringsAsFactors in the data.frame will work but it
looks like it should


--- "Li, Yan (IED)" <Yan.Y.Li at MorganStanley.com>
wrote:

> Hi all,
> 
> I was trying to convert a data frame to a zoo object
> so I can use some
> time series functions like lag(). But it seems then
> everything became a
> factor, so I have to convert it back to numeric to
> run the correct
> regressions. Is there a way to avoid it? Here is an
> example:
> 
> #############################
> a <- data.frame(nn =as.character(c("a", "b", "c",
> "d")), dd =
> as.Date("2007-08-01")+ c(1,2,3,4), x = rnorm(4), y =
> rnorm(4))
> a
> str(a)
> 
> 
> b <- zoo(a, order.by = a$dd)
> b
> str(b)
> 
> c <- data.frame(b)
> str(c)
> 
> #############################################333
> Results of this example:
> > a
>   nn         dd      x      y
> 1  a 2007-08-02  0.388 -0.394
> 2  b 2007-08-03 -0.054 -0.059
> 3  c 2007-08-04 -1.377  1.100
> 4  d 2007-08-05 -0.415  0.763
> > str(a)
> 'data.frame':   4 obs. of  4 variables:
>  $ nn: Factor w/ 4 levels "a","b","c","d": 1 2 3 4
>  $ dd:Class 'Date'  num [1:4] 13727 13728 13729
> 13730
>  $ x : num   0.3877 -0.0538 -1.3771 -0.4150
>  $ y : num  -0.3943 -0.0593  1.1000  0.7632
> > b <- zoo(a, order.by = a$dd)
> > b
>            nn dd         x      y     
> 2007-08-02 a  2007-08-02  0.388 -0.394
> 2007-08-03 b  2007-08-03 -0.054 -0.059
> 2007-08-04 c  2007-08-04 -1.377  1.100
> 2007-08-05 d  2007-08-05 -0.415  0.763
> > str(b)
>  chr [1:4, 1:4] "a" "b" "c" "d" "2007-08-02"
> "2007-08-03" ...
>  - attr(*, "dimnames")=List of 2
>   ..$ : chr [1:4] "1" "2" "3" "4"
>   ..$ : chr [1:4] "nn" "dd" "x" "y"
>  - attr(*, "index")=Class 'Date'  num [1:4] 13727
> 13728 13729 13730
> > 
> > c <- data.frame(b)
> > str(c)
> 'data.frame':   4 obs. of  4 variables:
>  $ nn: Factor w/ 4 levels "a","b","c","d": 1 2 3 4
>   ..- attr(*, "names")= chr  "1" "2" "3" "4"
>  $ dd: Factor w/ 4 levels
> "2007-08-02","2007-08-03",..: 1 2 3 4
>   ..- attr(*, "names")= chr  "1" "2" "3" "4"
>  $ x : Factor w/ 4 levels " 0.388","-0.054",..: 1 2
> 4 3
>   ..- attr(*, "names")= chr  "1" "2" "3" "4"
>  $ y : Factor w/ 4 levels " 0.763"," 1.100",..: 4 3
> 2 1
>   ..- attr(*, "names")= chr  "1" "2" "3" "4"
> ##################################3
> So after converting to zoo, all the variables became
> factors. How can I
> keep this from happening? Thank you very much for
> any advice.
> 
> Yan
>
--------------------------------------------------------
> 
> This is not an offer (or solicitation of an offer)
> to bu...{{dropped:22}}
> 
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