My question must be a trivial one.
There is automatic coercicion to vector when extracting only one line of a
matrix.
# example
A = matrix(1:12,3,4)
rownames(A) = c('a1','a2','a3')
i = 1:2
A[i,]
# [,1] [,2] [,3] [,4]
# a1 1 4 7 10 matrix
# a2 2 5 8 11
i = 1
A[i,]
# [1] 1 4 7 10 vector !!!
# to get the rowname, it is necessary to do
rownames(A)[i]
# [1] "a1"
Is it possible to get a (1,4)-matrix (without testing length(i) ) ? I see
nothing in options()...
Jean Coursol
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