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Message-ID: <6b8e7231-b0a3-37d3-1d60-598b5bdcdbdc@math.uni-giessen.de>
Date: 2021-02-18T17:01:28Z
From: Gerrit Eichner
Subject: Concatenation?
In-Reply-To: <CAGxFJbT3x8hEx9OX61kr023+4F-SD7Q6eGSU2F1WkS5JypLxgQ@mail.gmail.com>

Right, Bert, but not if X is "only"  matrix. ;-)

 > X <- cbind(X1 = letters[1:3],
            X2 = 5:7,
            X3 = LETTERS[1:3]
)
 > do.call(paste0, X)
Fehler in do.call(paste0, X) : das zweite Argument muss eine Liste sein

(Sorry, but my system is German. :-))

But, of course, then, e.g.,

do.call(paste0, data.frame(X))

would work.

  Best  --  Gerrit

---------------------------------------------------------------------
Dr. Gerrit Eichner                   Mathematical Institute, Room 212
gerrit.eichner at math.uni-giessen.de   Justus-Liebig-University Giessen
Tel: +49-(0)641-99-32104          Arndtstr. 2, 35392 Giessen, Germany
http://www.uni-giessen.de/eichner
---------------------------------------------------------------------

Am 18.02.2021 um 17:08 schrieb Bert Gunter:
> Inline comment below.
> Cheers,
> Bert
> 
> Bert Gunter
> 
> "....
> or, if stored as columns of a matrix or data frame X, e.g.,
> 
> 
> ##############
> 
>     apply(X, 1, paste0)
> 
> ##############
> "
> No. paste() is vectorized. apply() can be avoided:
>> df? <- data.frame(X1 = letters[1:3],
>  ? ? ? ? ? ? ? ?? X2 = 5:7,
>  ? ? ? ? ? ? ? ? ?X3 = LETTERS[1:3]
> )
>> df
>  ? X1 X2 X3
> 1 ?a ?5 ?A
> 2 ?b ?6 ?B
> 3 ?c ?7 ?C
> 
>> do.call(paste0, df)
> [1] "a5A" "b6B" "c7C"
> 
> 
> 
>      ? Hth? --? Gerrit
> 
>     ---------------------------------------------------------------------
>     Dr. Gerrit Eichner? ? ? ? ? ? ? ? ? ?Mathematical Institute, Room 212
>     gerrit.eichner at math.uni-giessen.de
>     <mailto:gerrit.eichner at math.uni-giessen.de> 
>      ?Justus-Liebig-University Giessen
>     Tel: +49-(0)641-99-32104? ? ? ? ? Arndtstr. 2, 35392 Giessen, Germany
>     Fax: +49-(0)641-99-32109 http://www.uni-giessen.de/eichner
>     <http://www.uni-giessen.de/eichner>
>     ---------------------------------------------------------------------
> 
>     Am 17.02.2021 um 22:09 schrieb Parkhurst, David:
>      > If I have a vector of site abbreviations and a vector of depths
>     in those water bodies, is there a simple way in R to combine them to
>     make a third vector?
>      > Examples:
>      >
>      > site? depth? ? ? ? ? ?desired
>      > MU? ? 0? ? ? ? ? ? ? ?MU0
>      > MU? ? 1? ? ? ? ? ? ? ?MU1
>      > MU? ? 2? ? ? ? ? ? ? ?MU2
>      > MC? ? 0? ? ? ? ? ? ? ?MC0
>      > MC? ? 1? ? ? ? ? ? ? ?MC1
>      > MC? ? 2? ? ? ? ? ? ? ?MC2
>      >
>      > The dataset has many more lines than this.? I can see how to do
>     this with lots of if statements, but does R have magic that can make
>     it happen easily?? I guess this would be called concatenation.
>      >
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>      >
> 
>     ______________________________________________
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>