The GHSOM Toolbox contains several functions to train, visualize
and label a GHSOM. Most functions rely on some functions of the
For details on each function try typing "help <function>
" or for
full details try "type <function>
" after installing the toolbox,
in the Matlab environment.
The functions of the GHSOM Toolbox are categorized in:
The main training function is "ghsom_train".
This function calls all other necessary training functions as needed.
The other training functions are "ghsom_train_grow",
There are several options available such as the orientation
of sublayers, the initialization of the different layers, and
the type of error calculated.
There are basically three options for labeling a GHSOM.
The first "ghsom_datalabels" labels each map unit
with the names of the data items. The "ghsom_labelsom"
and "ghsom_websom" functions label the map units
based on the attributes they represent.
There are two visualization functions which normally would be
used subsequently. The first function "ghsom_visualize_grid"
draws the basic GHSOM structure and adds coloring
(e.g. component planes or hierarchy level) if desired.
The second function "ghsom_visualize_labels" adds the map labels on top
of the ghsom grid. Alternatively, the model vectors can be visualized - if they represent 2-dimensional time series data - using "ghsom_visualize_2dts".
All Matlab data structures can be stored using the Matlab commands
"save <filename> <variable1> <variable2> ..."
(and "load <filename>" to load stored variables).
An external interface for the SOM_PAK data format is supplied
by the functions "ghsom_write_cods" and
To demonstrate the usage and some of the possibilities a
few demonstrations are supplied with the toolbox. The functions are
"ghsom_demo2", "ghsom_demo3", and "ghsom_demo4". For details
on how the demonstrations call other functions use
The demonstrations with documentation
are available on this web page.
There are 2 functions which are used by other functions, namely
"ghsom_idx2data" and "ghsom_map_data".
The first is needed to obtain the sub dataset belonging to a
sub-map of GHSOM structure. The second is necessary when
reading data from the SOM_PAK interface.
Furthermore, a test dataset is supplied which has been published
by Kohonen and contains some animals ("animals.dat"), a dataset consisting of 77 pieces of music ("music.mat"), and a dataset representing musical performances of Chopin pieces ("worms.mat").