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simple coversion of matrix rows to matrix columns

Hi,


?is.matrix(a)
#[1] TRUE
#You don't need t(matrix(a))

t(a)
#???? [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
#[1,]??? 1??? 2??? 3??? 4??? 5??? 6??? 7??? 8??? 9??? 10
#[2,]?? 11?? 12?? 13?? 14?? 15?? 16?? 17?? 18?? 19??? 20
#[3,]?? 21?? 22?? 23?? 24?? 25?? 26?? 27?? 28?? 29??? 30
is.matrix(t(a))
#[1] TRUE


str(t(a))
# int [1:3, 1:10] 1 11 21 2 12 22 3 13 23 4 ...
str(t(matrix(a)) )
# int [1, 1:30] 1 2 3 4 5 6 7 8 9 10 ...

A.K.

----- Original Message -----
From: Andras Farkas <motyocska at yahoo.com>
To: "r-help at r-project.org" <r-help at r-project.org>
Cc: 
Sent: Wednesday, November 7, 2012 6:50 AM
Subject: [R] simple coversion of matrix rows to matrix columns

Dear All
?
I would like to convert matrix rows to columns. I am thinking the t() function should help, but am having a hard time converting the matrix into the dimensions I would like them to. Example:
?
a <-matrix(c(1:30),ncol=3) gives me:[,1] [,2] [,3]
 [1,]? ? 1?  11?  21
 [2,]? ? 2?  12?  22
 [3,]? ? 3?  13?  23
 [4,]? ? 4?  14?  24
 [5,]? ? 5?  15?  25
 [6,]? ? 6?  16?  26
 [7,]? ? 7?  17?  27
 [8,]? ? 8?  18?  28
 [9,]? ? 9?  19?  29
[10,]?  10?  20?  30
?
I would like to convert the above into a matrix that looks like this with 3 rows and 10 columns:
?
1? ?  2?  3?  4?  5?  6?  7?  8?  9? 10
11?  12? 13? 14? 15? 16? 17? 18? 19? 20
21?  22? 23? 24? 25? 26? 27? 28? 29? 30
?
I have tried : 
b <-t(matrix(a))
?
but I am getting a 1X30 double matrix. I also Tried to specify 
b <-t(matrix(a),byrow=TRUE,ncol=10)
but that does not help either...
?
?
?
?
apreciate your help,
?
?
?
Andras
??? [[alternative HTML version deleted]]


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