R/hypergraph_from_spectral_clustering.R

In HyperG: Hypergraphs in R

## HyperG R Package
## 
## Copyright (c) 2021 David J. Marchette <dmarchette@gmail.com>
## 
## Permission is hereby granted, free of charge, to any person obtaining a copy
## of this software and associated documentation files (the "Software"), to deal
## in the Software without restriction, including without limitation the rights
## to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
## copies of the Software, and to permit persons to whom the Software is
## furnished to do so, subject to the following conditions:
## 
## The above copyright notice and this permission notice shall be included in all
## copies or substantial portions of the Software.
## 
## THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
## IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
## FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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## SOFTWARE.
## 

hypergraph_from_fuzzy_clustering <-
function(z,threshold)
{
	if(missing(threshold)){
		threshold <- 1/ncol(z)
	}
	M <- Matrix::Matrix(0,nrow=nrow(z),ncol=ncol(z))
	M[z>=threshold] <- 1
	hypergraph_from_incidence_matrix(M)
}

hypergraph_from_spectral_clustering <-
function(g,
															  m,
                                               fuzzy=FALSE,
															  threshold,
															  ...)
{
   if(missing(m)){
	   m <- cluster_spectral(g,...)
	}
	if(fuzzy){
	   z <- t(m$z)
		if(missing(threshold)){
			threshold <- 1/m$G
		}
		return(hypergraph_from_fuzzy_clustering(z,threshold=threshold))
	} else {
	   return(hypergraph_from_membership(m$classification))
	}
}