classvec2classmat {kohonen}

Convert a classification vector into a matrix or the other way around.

Description

Functions toggle between a matrix representation, where class membership is indicated with one '1' and for the rest zeros at each row, and a factor. The classification matrix contains one column per class. Conversion from a class matrix to a class vector assigns each row to the column with the highest value. An optional argument can be used to assign only those objects that have a probability higher than a certain threshold (default is 0).

Usage

classvec2classmat(yvec)
classmat2classvec(ymat, threshold=0)

Arguments

yvec

class vector. Usually a factor; if it is a vector of integer values, it will be converted to a factor.

ymat

class matrix: every column corresponds to a class.

threshold

only classify into a class if the probability is larger than this threshold.

Value

classvec2classmat returns the classification matrix, where each column consists of zeros and ones; classmat2classvec returns a factor.

Author(s)

Ron Wehrens

See Also

som,xyf,supersom

Examples

classes <- c(rep(1, 5), rep(2, 7), rep(3, 9))
classmat <- classvec2classmat(classes)
classmat
classmat2classvec(classmat)