costMatrix {tilingArray}R Documentation

Segmentation cost matrix

Description

This function calculates the cost matrix for the segmentation model

Usage

costMatrix(x, maxk)

Arguments

x Numeric vector of length n or matrix with n rows and d columns, where n is the number of sample points and d the number of replicate measurements (e.g. from multiple arrays).
maxk Positive integer.

Details

See the package vignette Calculation of the cost matrix.

Value

Matrix with maxk rows and length(x) columns.

Author(s)

W. Huber

Examples

d = 4
x = apply(matrix(rnorm(200), ncol=d), 2, cumsum)
maxk = 50
 
G = costMatrix(x, maxk=maxk)
 
G.pedestrian = matrix(NA, nrow=nrow(G), ncol=ncol(G))
for(i in 1:(ncol(G)))
  for(k in 1:min(nrow(G), nrow(x)-i+1))
    G.pedestrian[k, i] = (k*d-1)*var(as.vector(x[i:(i+k-1), ]))
 
stopifnot(identical(is.na(G), is.na(G.pedestrian)))
stopifnot(max(abs(G-G.pedestrian), na.rm=TRUE) <= 1e-6)

[Package tilingArray version 1.20.0 Index]