addDist {rrp} | R Documentation |
Adds constant to the elements of a dist object vector-wise. The idea is that a
symmetrix matrix M
can be represented as a triangular object {d}. With
this function you set M[x,x] = M[x,x] + k
but instead of working on
M
this function works on its dist
representation d
.
addDist(d, x, k)
d |
a dist object, upper diagonal, representing a symmetric matrix |
x |
a vector of indices |
k |
the constant to add |
returns the modified dist object
Stefano M. Iacus
M <- matrix(1:100,5,20) M <- M d <- as.dist(M) x <- 1:3 addDist(d,x,-80000) d # which is the equivalent of (apart for the diagonal elements) M[x,x] <- M[x,x] - 80000 # Indeed, we have d as.dist(M)