This is a modified version of cmdscale
that uses the Lanczos
procedure (slanczos
) instead of eigen
. Called by
smooth.construct.pco.smooth.spec
.
cmdscale_lanczos(d, k = 2, eig = FALSE, add = FALSE, x.ret = FALSE)
a distance structure as returned by dist
, or a full
symmetric matrix of distances or dissimilarities.
the maximum dimension of the space which the data are to be
represented in; must be in {1, 2, ..., n-1}
.
logical indicating whether eigenvalues should be returned.
logical indicating if the additive constant of Cailliez (1983) should be computed, and added to the non-diagonal dissimilarities such that the modified dissimilarities are Euclidean.
indicates whether the doubly centred symmetric distance matrix should be returned.
as cmdscale
Cailliez, F. (1983). The analytical solution of the additive constant problem. Psychometrika, 48, 343-349.