request: How to get column name
On 9/3/2008 11:05 AM, Petr PIKAL wrote:
r-help-bounces at r-project.org napsal dne 03.09.2008 15:54:08:
try this: x <- c(3,3,3,3,0,0,0,0,5,5,5,5,8,8,8,8) x <- matrix(x, nrow=4) which(colSums(x == 0) == nrow(x))
Isn't this the same? which(colSums(x)==0)
No, because the column sum can be zero without each element being zero: x <- c(3,3,3,3,1,-1,1,-1,5,5,5,5,8,8,8,8) x <- matrix(x, nrow=4)
which(colSums(x == 0) == nrow(x))
integer(0)
which(colSums(x)==0)
[1] 2
Regards Petr
I hope it helps. Best, Dimitris Muhammad Azam wrote:
Dear R community I have a problem regarding which of the column in a matrix contains
all of
zero elements. e.g.
x=c(3,3,3,3,0,0,0,0,5,5,5,5,8,8,8,8); x=matrix(x, nrow=4) the output is
x
[,1] [,2] [,3] [,4] [1,] 3 0 5 8 [2,] 3 0 5 8 [3,] 3 0 5 8 [4,] 3 0 5 8 In this case the required column is second so the result should be
"2". How
can i get it?
best regards Muhammad Azam [[alternative HTML version deleted]]
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