sammon {smacofx}

Wrapper to sammon for S3 class

Description

Wrapper to sammon for S3 class

Usage

sammon(d, y = NULL, k = 2, ...)

Arguments

d

a distance structure such as that returned by 'dist' or a full symmetric matrix. Data are assumed to be dissimilarities or relative distances, but must be positive except for self-distance. This can contain missing values.

y

An initial configuration. If NULL, cmdscale is used to provide the classical solution. (If there are missing values in 'd', an initial configuration must be provided.) This must not have duplicates.

k

The dimension of the configuration

...

Additional parameters passed to sammon, see sammon

Details

Overloads MASS::sammon and adds new slots and class attributes for which there are methods.

Value

Object of class 'sammonx' inheriting from sammon. This wrapper adds an extra slot to the list with the call, adds column labels to the $points, adds slots conf=points, delta=d, dhat=normalized dissimilarities, confdist=distance between points in conf, stress.m=stress, stress=sqrt(stress.m) and assigns S3 classes 'sammonx', 'sammon' and 'cmdscalex'.

Examples

dis<-as.matrix(smacof::kinshipdelta)
res<-sammon(dis)