[R] error in duplicated() man page

[Bert Gunter]

Juan:
No, I think there may be a bug:

> duplicated(array(c(1,2,3,2,5,6),c(3,2)), MARGIN=1:2)
      [,1]  [,2]
[1,] FALSE  TRUE
[2,] FALSE FALSE
[3,] FALSE FALSE
## This is wrong

## But if we first define the array...
> a <- array(c(1,2,3,4,5,6), c(3,2))
> duplicated(a, MARGIN = 1:2)
      [,1]  [,2]
[1,] FALSE FALSE
[2,] FALSE FALSE
[3,] FALSE FALSE
## This is right

I'll wait a bit before filing a bug report so that any error I may be
making can be pointed out (note that my R version is NOT current, so I need
to update).

> sessionInfo()
R version 3.5.2 (2018-12-20)
Platform: x86_64-apple-darwin15.6.0 (64-bit)
Running under: macOS Mojave 10.14.4

Matrix products: default
BLAS:
/System/Library/Frameworks/Accelerate.framework/Versions/A/Frameworks/vecLib.framework/Versions/A/libBLAS.dylib
LAPACK:
/Library/Frameworks/R.framework/Versions/3.5/Resources/lib/libRlapack.dylib

locale:
[1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base

loaded via a namespace (and not attached):
[1] compiler_3.5.2 tools_3.5.2

Bert Gunter

"The trouble with having an open mind is that people keep coming along and
sticking things into it."
-- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )


On Thu, May 9, 2019 at 8:10 AM Juan Gomez <juangomezduaso using gmail.com> wrote:

> I think there is an error in duplicated() help page when it states that:
> "The array method calculates for each element of the sub-array
> specified by MARGIN if the remaining dimensions are identical to those
> for an earlier (or later, when fromLast = TRUE) element (in row-major
> order). "
> Instead of:
> "... (in column-major order)"
>
> For instance:
> duplicated(array(c(1,2,3,2,5,6),c(3,2)), MARGIN=1:2)
>       [,1]  [,2]
> [1,] FALSE  TRUE
> [2,] FALSE FALSE
> [3,] FALSE FALSE
> >
>
> ______________________________________________
> R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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.
>

	[[alternative HTML version deleted]]