Dear R-users,

I am somewhat puzzled by how R treats data frames with nested data frames. 
Below are a couple of examples, maybe someone could help explain what the 
guiding logic here is.

## construct plain data frame
> z <- data.frame(x=1)

## add a data frame member
> z$y <- data.frame(a=1,b=2)

## puzzle 1: z is apparently different from a straightforward construction of 
the 'same' object
> all.equal(z, data.frame(x=1,y=data.frame(a=1,b=2)))
[1] "Names: 1 string mismatch"                                                  
     "Length mismatch: comparison on first 2 components"
[3] "Component 2: Modes: list, numeric"                                         
     "Component 2: names for target but not for current"
[5] "Component 2: Attributes: < Modes: list, NULL >"                            
     "Component 2: Attributes: < names for target but not for current >"
[7] "Component 2: Attributes: < Length mismatch: comparison on first 0 
components >" "Component 2: Length mismatch: comparison on first 1 components"

## puzzle 2: could not rbind z
> rbind.data.frame(z, z)
Error in `row.names<-.data.frame`(`*tmp*`, value = c("1", "1")) :
  duplicate 'row.names' are not allowed
In addition: Warning message:
non-unique value when setting 'row.names': '1'

> version
               _
platform       i386-pc-mingw32
arch           i386
os             mingw32
system         i386, mingw32
status
major          2
minor          9.1
year           2009
month          06
day            26
svn rev        48839
language       R
version.string R version 2.9.1 (2009-06-26)


Thanks,
Vadim

Note: This email is for the confidential use of the named addressee(s) only and 
may contain proprietary, confidential or privileged information. If you are not 
the intended recipient, you are hereby notified that any review, dissemination 
or copying of this email is strictly prohibited, and to please notify the 
sender immediately and destroy this email and any attachments.  Email 
transmission cannot be guaranteed to be secure or error-free.  Jump Trading, 
therefore, does not make any guarantees as to the completeness or accuracy of 
this email or any attachments.  This email is for informational purposes only 
and does not constitute a recommendation, offer, request or solicitation of any 
kind to buy, sell, subscribe, redeem or perform any type of transaction of a 
financial product.

______________________________________________
R-help@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.

Reply via email to