# [R] binding rows from different matrices

Stephane DRAY stephane.dray at umontreal.ca
Tue Jun 29 17:00:29 CEST 2004

```Hello list,
I have 3 matrices with same dimension :
> veca=matrix(1:25,5,5)
> vecb=matrix(letters[1:25],5,5)
> vecc=matrix(LETTERS[1:25],5,5)

I would like to obtain a new matrix composed by alternating rows of these
different matrices (row 1 of mat 1, row 1 of mat 2, row 1 of mat 3, row 2
of mat 1.....)

I have found a solution to do it but it is not very pretty and I wonder if
I can do it in an other way (perhaps with apply ) ?

> res=matrix(0,1,5)
> for(i in 1:5)
+ res=rbind(res,veca[i,],vecb[i,],vecc[i,])
> res=res[-1,]
> res
[,1] [,2] [,3] [,4] [,5]
[1,] "1"  "6"  "11" "16" "21"
[2,] "a"  "f"  "k"  "p"  "u"
[3,] "A"  "F"  "K"  "P"  "U"
[4,] "2"  "7"  "12" "17" "22"
[5,] "b"  "g"  "l"  "q"  "v"
[6,] "B"  "G"  "L"  "Q"  "V"
[7,] "3"  "8"  "13" "18" "23"
[8,] "c"  "h"  "m"  "r"  "w"
[9,] "C"  "H"  "M"  "R"  "W"
[10,] "4"  "9"  "14" "19" "24"
[11,] "d"  "i"  "n"  "s"  "x"
[12,] "D"  "I"  "N"  "S"  "X"
[13,] "5"  "10" "15" "20" "25"
[14,] "e"  "j"  "o"  "t"  "y"
[15,] "E"  "J"  "O"  "T"  "Y"
>

Thanks in advance !

Stéphane DRAY
--------------------------------------------------------------------------------------------------

Département des Sciences Biologiques
Université de Montréal, C.P. 6128, succursale centre-ville
Montréal, Québec H3C 3J7, Canada

Tel : 514 343 6111 poste 1233
E-mail : stephane.dray at umontreal.ca
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Web                                          http://www.steph280.freesurf.fr/

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