Say I have:> set.seed( 1 ) > m <- matrix( runif(5^2), nrow=5, dimnames = list( c("A","B","C","D","E"), > c("O","P","Q","R","S") ) ) > mO P Q R S A 0.2655087 0.89838968 0.2059746 0.4976992 0.9347052 B 0.3721239 0.94467527 0.1765568 0.7176185 0.2121425 C 0.5728534 0.66079779 0.6870228 0.9919061 0.6516738 D 0.9082078 0.62911404 0.3841037 0.3800352 0.1255551 E 0.2016819 0.06178627 0.7698414 0.7774452 0.2672207 ------------------------------------------------------------------------------------------- I want to create a vector v from matrix m that looks like this: A.O 0.2655087 B.O 0.3721239 v <- as.vector( m ) almost gives me what I want, but then I need to take combinations of colnames( m ) and rownames( m ) to get my labels and hope they match up in order: if not, manipulate the order. This approach feels kludgy... Is this the right approach or is there a better way? -- View this message in context: http://www.nabble.com/Converting-a-Matrix-to-a-Vector-tp22696267p22696267.html Sent from the R help mailing list archive at Nabble.com.
try this:
set.seed(1)
m <- matrix(runif(5^2), nrow = 5,
dimnames =
list(c("A","B","C","D","E"),
c("O","P","Q","R","S")))
v <- c(m)
names(v) <- paste(rownames(m), colnames(m)[col(m)], sep = ".")
# or
# names(v) <- outer(rownames(m), colnames(m), paste, sep = ".")
v
I hope it helps.
Best,
Dimitris
Ken-JP wrote:> Say I have:
>
>> set.seed( 1 )
>> m <- matrix( runif(5^2), nrow=5, dimnames = list(
c("A","B","C","D","E"),
>>
c("O","P","Q","R","S") ) )
>> m
> O P Q R S
> A 0.2655087 0.89838968 0.2059746 0.4976992 0.9347052
> B 0.3721239 0.94467527 0.1765568 0.7176185 0.2121425
> C 0.5728534 0.66079779 0.6870228 0.9919061 0.6516738
> D 0.9082078 0.62911404 0.3841037 0.3800352 0.1255551
> E 0.2016819 0.06178627 0.7698414 0.7774452 0.2672207
>
>
-------------------------------------------------------------------------------------------
>
> I want to create a vector v from matrix m that looks like this:
>
> A.O 0.2655087
> B.O 0.3721239
>
> v <- as.vector( m ) almost gives me what I want, but then I need to take
> combinations of colnames( m ) and rownames( m ) to get my labels and hope
> they match up in order: if not, manipulate the order. This approach feels
> kludgy...
>
> Is this the right approach or is there a better way?
>
>
>
--
Dimitris Rizopoulos
Assistant Professor
Department of Biostatistics
Erasmus University Medical Center
Address: PO Box 2040, 3000 CA Rotterdam, the Netherlands
Tel: +31/(0)10/7043478
Fax: +31/(0)10/7043014
G'day Ken, On Wed, 25 Mar 2009 00:13:48 -0700 (PDT) Ken-JP <kfmfe04 at gmail.com> wrote:> > Say I have: > > > set.seed( 1 ) > > m <- matrix( runif(5^2), nrow=5, dimnames > > list( c("A","B","C","D","E"), c("O","P","Q","R","S") ) ) > > m > O P Q R S > A 0.2655087 0.89838968 0.2059746 0.4976992 0.9347052 > B 0.3721239 0.94467527 0.1765568 0.7176185 0.2121425 > C 0.5728534 0.66079779 0.6870228 0.9919061 0.6516738 > D 0.9082078 0.62911404 0.3841037 0.3800352 0.1255551 > E 0.2016819 0.06178627 0.7698414 0.7774452 0.2672207 > > ------------------------------------------------------------------------------------------- > > I want to create a vector v from matrix m that looks like this: > > A.O 0.2655087 > B.O 0.3721239 > > v <- as.vector( m ) almost gives me what I want, but then I need to > take combinations of colnames( m ) and rownames( m ) to get my labels > and hope they match up in order: if not, manipulate the order. This > approach feels kludgy... > > Is this the right approach or is there a better way?R> tt <- reshape(data.frame(m), direction="long", varying=list(1:5), ids=rownames(m), times=colnames(m)) R> ind <- names(tt) %in% c("time", "id") R> uu <- tt[,!ind] R> names(uu) <- rownames(tt) R> uu A.O B.O C.O D.O E.O A.P B.P 0.26550866 0.37212390 0.57285336 0.90820779 0.20168193 0.89838968 0.94467527 C.P D.P E.P A.Q B.Q C.Q D.Q 0.66079779 0.62911404 0.06178627 0.20597457 0.17655675 0.68702285 0.38410372 E.Q A.R B.R C.R D.R E.R A.S 0.76984142 0.49769924 0.71761851 0.99190609 0.38003518 0.77744522 0.93470523 B.S C.S D.S E.S 0.21214252 0.65167377 0.12555510 0.26722067 HTH. Cheers, Berwin =========================== Full address ============================Berwin A Turlach Tel.: +65 6516 4416 (secr) Dept of Statistics and Applied Probability +65 6516 6650 (self) Faculty of Science FAX : +65 6872 3919 National University of Singapore 6 Science Drive 2, Blk S16, Level 7 e-mail: statba at nus.edu.sg Singapore 117546 http://www.stat.nus.edu.sg/~statba
Use the 'reshape' package:> library(reshape) > melt(m)X1 X2 value 1 A O 0.26550866 2 B O 0.37212390 3 C O 0.57285336 4 D O 0.90820779 5 E O 0.20168193 6 A P 0.89838968 7 B P 0.94467527 8 C P 0.66079779 9 D P 0.62911404 10 E P 0.06178627 11 A Q 0.20597457 12 B Q 0.17655675 13 C Q 0.68702285 14 D Q 0.38410372 15 E Q 0.76984142 16 A R 0.49769924 17 B R 0.71761851 18 C R 0.99190609 19 D R 0.38003518 20 E R 0.77744522 21 A S 0.93470523 22 B S 0.21214252 23 C S 0.65167377 24 D S 0.12555510 25 E S 0.26722067>On Wed, Mar 25, 2009 at 3:13 AM, Ken-JP <kfmfe04 at gmail.com> wrote:> > Say I have: > >> set.seed( 1 ) >> m <- matrix( runif(5^2), nrow=5, dimnames = list( c("A","B","C","D","E"), >> c("O","P","Q","R","S") ) ) >> m > ? ? ? ? ?O ? ? ? ? ?P ? ? ? ? Q ? ? ? ? R ? ? ? ? S > A 0.2655087 0.89838968 0.2059746 0.4976992 0.9347052 > B 0.3721239 0.94467527 0.1765568 0.7176185 0.2121425 > C 0.5728534 0.66079779 0.6870228 0.9919061 0.6516738 > D 0.9082078 0.62911404 0.3841037 0.3800352 0.1255551 > E 0.2016819 0.06178627 0.7698414 0.7774452 0.2672207 > > ------------------------------------------------------------------------------------------- > > I want to create a vector v from matrix m that looks like this: > > A.O 0.2655087 > B.O 0.3721239 > > v <- as.vector( m ) almost gives me what I want, but then I need to take > combinations of colnames( m ) and rownames( m ) to get my labels and hope > they match up in order: if not, manipulate the order. ?This approach feels > kludgy... > > Is this the right approach or is there a better way? > > > > -- > View this message in context: http://www.nabble.com/Converting-a-Matrix-to-a-Vector-tp22696267p22696267.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. >-- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem that you are trying to solve?
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