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Message-ID: <F99A7BAA16F00E4FB872978F3F99137803AF97C6@VFGAMLAO13.Enterprise.afmc.ds.af.mil>
Date: 2009-04-15T18:33:51Z
From: Cable, Samuel B Civ USAF AFMC AFRL/RVBXI
Subject: (hopefully) simple array op
In-Reply-To: <mailman.25.1239789606.8943.r-help@r-project.org>

I have a multidimensional array "a", for example,

> a
, , 1

     [,1] [,2]
[1,]    1    3
[2,]    2    4

, , 2

     [,1] [,2]
[1,]    5    7
[2,]    6    8

So a is 2x2x2.

I have another array "b", for example,

> b
     [,1] [,2]
[1,]    9   11
[2,]   10   12

So b is 2x2.

I want to "tack" b onto a so that b becomes a new "plane", so to speak,
in a.  In other words, I want the result c to be:

> c
, , 1

     [,1] [,2]
[1,]    1    3
[2,]    2    4

, , 2

     [,1] [,2]
[1,]    5    7
[2,]    6    8

, , 3

     [,1] [,2]
[1,]    9   11
[2,]   10   12

I can think of a number of ways to do this, but they are all cumbersome.
Given R's facility with arrays and indices, it occurs to me that there
might be some "one-line" way to accomplish this.  Does anyone know if
there is?  Thanks.

--Sam