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# Processes the 'table' paramter to the constructor
#
sub _process_table { my $self = shift;
	$_ = $self->_process_input_text( $self->{table} );
	undef $self->{table};
	return $_;
}


__END__
1;

=head1 FILE FORMAT

This module has begun to attempt the I<SOM_PAK> format:
I<SOM_PAK> file format version 3.1 (April 7, 1995),
Helsinki University of Technology, Espoo:

=over 4

The input data is stored in ASCII-form as a list of entries, one line
...for each vectorial sample.

The first line of the file is reserved for status knowledge of the
entries; in the present version it is used to define the following
items (these items MUST occur in the indicated order):

   - Dimensionality of the vectors (integer, compulsory).
   - Topology type, either hexa or rect (string, optional, case-sensitive).
   - Map dimension in x-direction (integer, optional).
   - Map dimension in y-direction (integer, optional).
   - Neighborhood type, either bubble or gaussian (string, optional, case-sen-
      sitive).

...

Subsequent lines consist of n floating-point numbers followed by an
optional class label (that can be any string) and two optional
qualifiers (see below) that determine the usage of the corresponding
data entry in training programs.  The data files can also contain an
arbitrary number of comment lines that begin with '#', and are
ignored. (One '#' for each comment line is needed.)

If some components of some data vectors are missing (due to data
collection failures or any other reason) those components should be
marked with 'x'...[in processing, these] are ignored.

...

Each data line may have two optional qualifiers that determine the
usage of the data entry during training. The qualifiers are of the
form codeword=value, where spaces are not allowed between the parts of
the qualifier. The optional qualifiers are the following:

=over 4

=item -

Enhancement factor: e.g. weight=3.  The training rate for the
corresponding input pattern vector is multiplied by this
parameter so that the reference vectors are updated as if this
input vector were repeated 3 times during training (i.e., as if
the same vector had been stored 2 extra times in the data file).

=item -

Fixed-point qualifier: e.g. fixed=2,5.  The map unit defined by
the fixed-point coordinates (x = 2; y = 5) is selected instead of
the best-matching unit for training. (See below for the definition
of coordinates over the map.) If several inputs are forced to
known locations, a wanted orientation results in the map.

=back

=back

Not (yet) implimented in file format:

=over 4

=item *

hexa/rect is only visual, and only in the ::Demo::RGB package atm

=item *

I<neighbourhood type> is always gaussian.

=item *

i<x> for missing data.

=item *

the two optional qualifiers

=back

=cut

=head1 SEE ALSO

See L<AI::NeuralNet::Kohonen::Node/distance_from>;
L<AI::NeuralNet::Kohonen::Demo::RGB>.

L<The documentation for C<SOM_PAK>|ftp://cochlea.hut.fi/pub/som_pak>,
which has lots of advice on map building that may or may not be applicable yet.

A very nice explanation of Kohonen's algorithm:
L<AI-Junkie SOM tutorial part 1|http://www.fup.btinternet.co.uk/aijunkie/som1.html>

=head1 AUTHOR AND COYRIGHT

This implimentation Copyright (C) Lee Goddard, 2003-2006.
All Rights Reserved.

Available under the same terms as Perl itself.