[R] how to round only one column of a matrix ?

[Phil Spector]

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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