# nef: Negative Eigenfraction In maotai: Tools for Matrix Algebra, Optimization and Inference

## Description

Negative Eigenfraction (NEF) is a measure of distortion for the data whether they are lying in Euclidean manner or not. When the value is exactly 0, it means the data is Euclidean. On the other hand, when NEF is far away from 0, it means not Euclidean. The concept of NEF is closely related to the definiteness of a Gram matrix.

## Usage

 1 nef(data) 

## Arguments

 data an (n\times p) matrix whose rows are observations.

## Value

a nonnegative NEF value.

## References

\insertRef

pekalska_noneuclidean_2006maotai

## Examples

 1 2 3 4 5 6 ## use simple example of iris dataset data(iris) mydat = as.matrix(iris[,1:4]) ## calculate NEF nef(mydat) 

maotai documentation built on Feb. 3, 2022, 5:09 p.m.