Hi list I have a matrix of size m x n (m and n are different, hence non square!) I want to melt it in such a way that I get a df of 3 columns. m ,n and cell value in the original matrix. Any suggestions? -- *Chirag Gupta* Department of Crop, Soil, and Environmental Sciences, 115 Plant Sciences Building, Fayetteville, Arkansas 72701 [[alternative HTML version deleted]]
On 01/03/14 14:49, Chirag Gupta wrote:> Hi list > > I have a matrix of size m x n (m and n are different, hence non square!) > I want to melt it in such a way that I get a df of 3 columns. m ,nSurely you mean i, j (i = 1, ..., m), j = 1, ..., n).> and cell > value in the original matrix.Yes: dfX <- data.frame(i=as.vector(row(X)),j=as.vector(col(X)), value=as.vector(X)) where X is your matrix. The fact that X is non-square is of course completely irrelevant. cheers, Rolf Turner
library(reshape2)
mx <- matrix( 1:12, nrow=3 )
mxdf <- melt( mx )
names( mxdf ) <- c( "m", "n", "value" )
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On February 28, 2014 5:49:26 PM PST, Chirag Gupta <cxg040 at
email.uark.edu> wrote:>Hi list
>
>I have a matrix of size m x n (m and n are different, hence non
>square!)
>I want to melt it in such a way that I get a df of 3 columns. m ,n and
>cell
>value in the original matrix.
>
>Any suggestions?
Hi,
You could try:
#If mat1 is the matrix
dimnames(mat1) <- list(1:nrow(mat1),1:ncol(mat1))
setNames(as.data.frame.table(mat1),c("m","n","value"))
A.K.
On Friday, February 28, 2014 11:40 PM, Chirag Gupta <cxg040 at
email.uark.edu> wrote:
Hi list
I have a matrix of size m x n (m and n are different, hence non square!)
I want to melt it in such a way that I get a df of 3 columns. m ,n and cell
value in the original matrix.
Any suggestions?
--
*Chirag Gupta*
Department of Crop, Soil, and Environmental Sciences,
115 Plant Sciences Building, Fayetteville, Arkansas 72701
??? [[alternative HTML version deleted]]
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