Message-ID: <da79af330803091635t1765b672h67068e716dc73e57@mail.gmail.com>
Date: 2008-03-09T23:35:25Z
From: Henrique Dallazuanna
Subject: question about matrix one column values matching a vector of values
In-Reply-To: <8ee9d8f20803091622x6cbdc501q9a1ea8df2339879b@mail.gmail.com>
Use %in% indeed of '=='
a[a[,1] %in% b,]
On 09/03/2008, Waverley <waverley.paloalto at gmail.com> wrote:
> Hi,
>
> I have a matrix
> a = matrix (1:16, 4, 4)
> b = c (2,3)
>
> I want to find out which rows of a, where a[,1] equals any values of b?
>
> I know that if b is only one value, e.g, b=2, then what I want is a[a[,1] ==
> 2,]
>
> But what about if it is not one value but a vector of values?
>
> Thanks much in advance.
>
> --
> Waverley @ Palo Alto
>
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>
--
Henrique Dallazuanna
Curitiba-Paran?-Brasil
25? 25' 40" S 49? 16' 22" O