Dear all Is there a simpler method to achieve the following: When I obtain an empty data.frame after subsetting, I need for it to contain one line of NAs. Here's a dummy example:> (.xb <- iris[ iris$Species=='zz', ])[1] Sepal.Length Sepal.Width Petal.Length Petal.Width Species <0 rows> (or 0-length row.names)> dim(.xb)[1] 0 5> (.xa <- data.frame(matrix(rep(NA, ncol(.xb)), 1)))X1 X2 X3 X4 X5 1 NA NA NA NA NA> names(.xa) <- names(.xb) > (.xb <- .xa)Sepal.Length Sepal.Width Petal.Length Petal.Width Species 1 NA NA NA NA NA The solution I came up with is way too convoluted. Anything simpler? Regards Liviu -- Do you know how to read? http://www.alienetworks.com/srtest.cfm http://goodies.xfce.org/projects/applications/xfce4-dict#speed-reader Do you know how to write? http://garbl.home.comcast.net/~garbl/stylemanual/e.htm#e-mail
Hello,
If you write a function, it becomes less convoluted...
empty <- function(x){
if(NROW(x) == 0){
y <- rep(NA, NCOL(x))
names(y) <- names(x)
y
}else x
}
(.xb <- iris[ iris$Species=='zz', ])
empty(.xb)
Hope this helps,
Rui Barradas
Em 10-07-2012 14:15, Liviu Andronic escreveu:> Dear all
> Is there a simpler method to achieve the following: When I obtain an
> empty data.frame after subsetting, I need for it to contain one line
> of NAs. Here's a dummy example:
>> (.xb <- iris[ iris$Species=='zz', ])
> [1] Sepal.Length Sepal.Width Petal.Length Petal.Width Species
> <0 rows> (or 0-length row.names)
>> dim(.xb)
> [1] 0 5
>> (.xa <- data.frame(matrix(rep(NA, ncol(.xb)), 1)))
> X1 X2 X3 X4 X5
> 1 NA NA NA NA NA
>> names(.xa) <- names(.xb)
>> (.xb <- .xa)
> Sepal.Length Sepal.Width Petal.Length Petal.Width Species
> 1 NA NA NA NA NA
>
>
> The solution I came up with is way too convoluted. Anything simpler?
Regards
> Liviu
>
>
On Tue, Jul 10, 2012 at 9:15 AM, Liviu Andronic <landronimirc at gmail.com> wrote:> Dear all > Is there a simpler method to achieve the following: When I obtain an > empty data.frame after subsetting, I need for it to contain one line > of NAs. Here's a dummy example: >> (.xb <- iris[ iris$Species=='zz', ]) > [1] Sepal.Length Sepal.Width Petal.Length Petal.Width Species > <0 rows> (or 0-length row.names) >> dim(.xb) > [1] 0 5 >> (.xa <- data.frame(matrix(rep(NA, ncol(.xb)), 1))) > X1 X2 X3 X4 X5 > 1 NA NA NA NA NA >> names(.xa) <- names(.xb) >> (.xb <- .xa) > Sepal.Length Sepal.Width Petal.Length Petal.Width Species > 1 NA NA NA NA NA > > > The solution I came up with is way too convoluted. Anything simpler? Regards > Liviu >Try this: Try this:> iris[NaN,]Sepal.Length Sepal.Width Petal.Length Petal.Width Species NA NA NA NA NA <NA> -- Statistics & Software Consulting GKX Group, GKX Associates Inc. tel: 1-877-GKX-GROUP email: ggrothendieck at gmail.com
Hi, Try this: .xa<-iris[1,][rep(NA,length(iris),1),] .xa #?? Sepal.Length Sepal.Width Petal.Length Petal.Width Species #NA?????????? NA????????? NA?????????? NA????????? NA??? <NA> #or .xb<-iris[1,][rep(NA,ncol(iris),1),] ?.xb #?? Sepal.Length Sepal.Width Petal.Length Petal.Width Species #NA?????????? NA????????? NA?????????? NA????????? NA??? <NA> A.K. ----- Original Message ----- From: Liviu Andronic <landronimirc at gmail.com> To: "r-help at r-project.org Help" <r-help at r-project.org> Cc: Sent: Tuesday, July 10, 2012 9:15 AM Subject: [R] fill 0-row data.frame with 1 line of NAs Dear all Is there a simpler method to achieve the following: When I obtain an empty data.frame after subsetting, I need for it to contain one line of NAs. Here's a dummy example:> (.xb <- iris[ iris$Species=='zz', ])[1] Sepal.Length Sepal.Width? Petal.Length Petal.Width? Species <0 rows> (or 0-length row.names)> dim(.xb)[1] 0 5> (.xa <- data.frame(matrix(rep(NA, ncol(.xb)), 1)))? X1 X2 X3 X4 X5 1 NA NA NA NA NA> names(.xa) <- names(.xb) > (.xb <- .xa)? Sepal.Length Sepal.Width Petal.Length Petal.Width Species 1? ? ? ? ? NA? ? ? ? ? NA? ? ? ? ? NA? ? ? ? ? NA? ? ? NA The solution I came up with is way too convoluted. Anything simpler? Regards Liviu -- Do you know how to read? http://www.alienetworks.com/srtest.cfm http://goodies.xfce.org/projects/applications/xfce4-dict#speed-reader Do you know how to write? http://garbl.home.comcast.net/~garbl/stylemanual/e.htm#e-mail ______________________________________________ R-help at 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.