GWR and GNG Classifier

An extension for classification including 2 types of Neural Gas, the Growing When Required (GWR) and Growing Neural Gas (GNG). Based on (Konsoulas, 2013) see GNG_LICENSE - with a wrapper for the GNG and my own implementation of a GWR neural gas (Marsland et al., 2002) and a simple classifier as simplified version from what Parisi used see (Parisi, 2015).
Included there is a simple example of a classifier with 4 shapes (which is trivially classifiable with 4 nodes), to show how the gas constructs the topological description of a dataset.
Cite as:
Belmonte Klein, F., 2016. GWR and GNG Classifier - File Exchange - MATLAB Central. Plymouth University, Plymouth, England.

.bib:
@misc{belmonte_klein_gwr_2016,
address = {Plymouth, England},
title = {{GWR} and {GNG} {Classifier} - {File} {Exchange} - {MATLAB} {Central}},
copyright = {MIT License Copyright (c) 2016 Frederico Belmonte Klein},
shorttitle = {{GWR} and {GNG} {Classifier}},
url = {http://uk.mathworks.com/matlabcentral/fileexchange/57798-gwr-and-gng-classifier},
abstract = {A Growing When Required and Growing Neural Gas classifier},
urldate = {2016-06-22},
publisher = {Plymouth University},
author = {Belmonte Klein, Frederico},
month = June,
year = {2016}
}

References:

Konsoulas, I., 2013. Unsupervised Learning with Growing Neural Gas (GNG) Neural Network - File Exchange - MATLAB Central [WWW Document]. URL http://www.mathworks.com/matlabcentral/fileexchange/43665-unsupervised-learning-with-growing-neural-gas--gng--neural-network (accessed 6.22.16).

Marsland, S., Shapiro, J., Nehmzow, U., 2002. A self-organising network that grows when required. Neural Networks 15, 1041–1058.

Parisi, G.I., Weber, C., Wermter, S., 2015. Self-organizing neural integration of pose-motion features for human action recognition. Frontiers in Neurorobotics 9. doi:10.3389/fnbot.2015.00003