Hi,
This line of code does the trick:
a[,which(apply(a, 2, sum) != 0)]
cheers,
Paul
Alberto Lora M wrote:
Hi Everbody
Could somebody help me.?
I need to remove the columns where the sum of it components is equal to
zero.
For example
a<-matrix(c(0,0,0,0,0,0,0,1,0,1,0,0,0,0,0,0,0,0,1,1,0,0,1,0), ncol=4)
a
[,1] [,2] [,3] [,4]
[1,] 0 0 0 1
[2,] 0 1 0 1
[3,] 0 0 0 0
[4,] 0 1 0 0
[5,] 0 0 0 1
[6,] 0 0 0 0
Columns 1 and 3 should be removed
the result should be the dollowing matrix
[,2] [,4]
[1,] 0 1
[2,] 1 1
[3,] 0 0
[4,] 1 0
[5,] 0 1
[6,] 0 0
Thanks again
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Department of Physical Geography
Faculty of Geosciences
University of Utrecht
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