Message-ID: <4DB5BBDD.1030604@ucalgary.ca>
Date: 2011-04-25T18:22:21Z
From: Peter Ehlers
Subject: extracting names from matrix according to a condition
In-Reply-To: <BANLkTi=Hd5rwFxf01HiP4oj3zmNOy7Lt8A@mail.gmail.com>
On 2011-04-25 10:58, ivan wrote:
> Dear Community,
>
> I have a matrix with assigned colnames and rolnames as follows:
>
> A B
> NR 0.15 0,05
> AL 0,05 0,05
> . . .
> . . .
> . . .
>
> I want to extract the names of the rows for which A>0,1 and B<0,1. In
> the above example this would be observation NR only. Hence the output
> should write for instance:
>
> names:
> NR
>
> Is this possible? Thank you very much for your help.
Call the matrix m. Then
rownames(m[ m[, "A"] > 0.1 & m[, "B"] < 0.1, , drop=FALSE ])
should do what you want.
Peter Ehlers