smacof_forward_mds: Do forward MDS by using the SMACOF algorithm defined on page...

Description Usage Arguments Value

View source: R/forward_methods.R

Description

Do forward MDS by using the SMACOF algorithm defined on page 191 of Borg and Groenen.

Usage

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smacof_forward_mds(high_d, weights, dist.func = euclidean.dist,
  thresh = 1e-05, max.iters = 1000, n.inits = 10, seed = NULL,
  std = TRUE, symm = FALSE)

Arguments

high_d

The high dimensional data of which a low dimensional representation is desired, an n by p matrix where rows represent observations

dist.func

The distance function to be used for both low and high D distance computation.

thresh

The threshold below which stress must fall before computation ends.

max.iters

The maximum number of SMACOF iterations (i.e., the maximum number of times we solve the quadratic system described in chapter 8 of Borg and Groenen) per initialization.

n.inits

The number of times the SMACOF algorithm is run from a random configuration. This can be important, as the cost surface is highly nonconvex.

seed

Random seed used for initialization

symm

Boolean, is the distance function symmetric? We can save on computation if so.

low_d

The low_d solution, an n by 2 matrix, the cost of which is to be evaluated.

Value

List with $par, the optimal configuration as an n by 2 matrix, and $value as the stress of this configuration


NathanWycoff/mds.methods documentation built on May 23, 2019, 7:32 a.m.