help: how to get the position of a value in a matrix
Use which(..., arr.ind=TRUE); e.g.,
m <- matrix(runif(12), 3, 4) which(m > .8, arr.ind=TRUE)
row col [1,] 1 3 [2,] 2 3 [3,] 3 3 [4,] 3 4
m
[,1] [,2] [,3] [,4] [1,] 0.2148183 0.08251853 0.9444718 0.4487148 [2,] 0.5386863 0.49673282 0.8054240 0.5101593 [3,] 0.6252847 0.70974516 0.8858951 0.8590655 Andy
From: wu sz Hello, I have a data set matrix of 1200 * 15. How can I get the position of a specific value in the matrix? I use "seq(along = x)[x > value]" to look for the position of the value in the matrix, but "seq" can just find the sequence position row by row in the matrix, not a real position (like "rowNumber, colNumber"). Is any function for that? Thank you, Shengzhe
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