Is this what you're looking for?
> mymatrix =
matrix(rnorm(15),5,3,dimnames=list(NULL,c('x','y','z')))
> mymatrix
x y z
[1,] -0.4459162 -2.3936837 -0.7401963
[2,] 0.9886466 -1.3955161 -1.3390314
[3,] -0.2086743 1.7984620 -0.8532579
[4,] 1.0985411 0.9315553 -1.3981632
[5,] 0.5787438 0.1719177 0.2246174> mymatrix[,'y'] = round(mymatrix[,'y'])
> mymatrix
x y z
[1,] -0.4459162 -2 -0.7401963
[2,] 0.9886466 -1 -1.3390314
[3,] -0.2086743 2 -0.8532579
[4,] 1.0985411 1 -1.3981632
[5,] 0.5787438 0 0.2246174
- Phil Spector
Statistical Computing Facility
Department of Statistics
UC Berkeley
spector at stat.berkeley.edu
On Mon, 22 Nov 2010, madr wrote:
>
> round() function affects all values of a matrix, I want only to round
column
> that is called 'y'.
> --
> View this message in context:
http://r.789695.n4.nabble.com/how-to-round-only-one-column-of-a-matrix-tp3054363p3054363.html
> Sent from the R help mailing list archive at Nabble.com.
>
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