Message-ID: <B37C0A15B8FB3C468B5BC7EBC7DA14CC62F7AA37FA@LP-EXMBVS10.CO.IHC.COM>
Date: 2010-01-18T17:18:35Z
From: Greg Snow
Subject: Choose every second value
In-Reply-To: <4B52F26A.1040502@googlemail.com>
In addition to the other suggestions, you can use logical subsetting with autoreplication:
> x <- 1:6
> x[ c(T,F) ]
[1] 1 3 5
> x[ c(F,T) ]
[1] 2 4 6
--
Gregory (Greg) L. Snow Ph.D.
Statistical Data Center
Intermountain Healthcare
greg.snow at imail.org
801.408.8111
> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> project.org] On Behalf Of Walther, Alexander
> Sent: Sunday, January 17, 2010 4:20 AM
> To: r-help at r-project.org
> Subject: [R] Choose every second value
>
> Dear list,
>
> is there a command that selects every second value from a given vector?
> For instance,
>
> a <- c(1,2,3,4,5,6)
>
> should yield
>
> 1,3,5
>
> and
>
> 2,4,6
>
> which i intend to place into two seperate vectors.
>
>
> best
>
> Alex
>
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