Message-ID: <CAAmySGOdO2Cuavaeqf_8B0cyN4TpHCrm3ZPwV6dN7RtV5F_O0w@mail.gmail.com>
Date: 2012-07-17T22:08:57Z
From: R. Michael Weylandt
Subject: Finding the column with the maximum value by row
In-Reply-To: <CALrjt79wcCALA-4se+rUXDeg5gVKuki_JjFwgGaxu=0=_WgntQ@mail.gmail.com>
apply(a, 1, which.max)
Apply the which.max() function to the matrix a row-wise (1)
Michael
On Tue, Jul 17, 2012 at 5:03 PM, Christopher Desjardins
<cddesjardins at gmail.com> wrote:
> Hi,
> Let's say I have the following data:
>
>> a=matrix(c(1,2,4,4,2,1,1,2,4),nrow=3,byrow=T)
>
>> a
>
> [,1] [,2] [,3]
>
> [1,] 1 2 4
>
> [2,] 4 2 1
>
> [3,] 1 2 4
>
> What syntax should I use to get R to tell me the column that corresponds to
> the maximum value for each row?
>
> For my example, I would like to get a vector that says 3, 1, 3 because the
> maximum value for row 1 is in column 3, the maximum value for row 2 is in
> column 1, and the maximum value for row 3 is in column 3.
>
> Does that make sense?
>
> Please cc me if you reply!
>
> Chris
>
> [[alternative HTML version deleted]]
>
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