I would like to sort matrix3, so that every column in output matrix is
sorted. Also I have to unsort it later on.
matrix1-matrix(rnorm(100,354,78),ncol=10)
matrix2-matrix(rnorm(100,225,102),ncol=10)
matrix3-cbind(matrix1,matrix2)
nrCol-length(matrix3[1,])
class1-1:10
for(i in 1:nrCol)
{
Hi. Here is an example of sorting matrix columns:
mat - matrix(10:1, ncol=2, byrow=TRUE)
mat
[,1] [,2]
[1,] 109
[2,]87
[3,]65
[4,]43
[5,]21
apply(mat, 2, function(x) x[order(x)])
[,1] [,2]
[1,]21
[2,]43
[3,]65
[4,]8
Hello,
If I understand it correctly, the following should sort all columns of
matrix3 and then unsort the sorted matrix.
ord - apply(matrix3, 2, order)
# sort matrix3
mat4 - sapply(seq_len(ncol(ord)), function(i) matrix3[ord[,i], i])
mat4
# unsort mat4
mat5 - sapply(seq_len(ncol(ord)),
Hello,
Yes, you can do it like you say. Or you can unsort first and multiply later.
mat5.1 - sapply(seq_len(ncol(ord)), function(i) mat4[order(ord[,i]), i])
multip-mat4*2
mat5.2 - sapply(seq_len(ncol(ord)), function(i) multip[order(ord[,i]), i])
identical(mat5.1*2, mat5.2) #TRUE
Also, it's
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