AI-NNEasy

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lib/AI/NNEasy.pm  view on Meta::CPAN

#############################################################################
## This file was generated automatically by Class::HPLOO/0.21
##
## Original file:    ./lib/AI/NNEasy.hploo
## Generation date:  2005-01-16 22:07:24
##
## ** Do not change this file, use the original HPLOO source! **
#############################################################################

#############################################################################
## Name:        NNEasy.pm
## Purpose:     AI::NNEasy
## Author:      Graciliano M. P. 
## Modified by:
## Created:     2005-01-14
## RCS-ID:      
## Copyright:   (c) 2005 Graciliano M. P. 
## Licence:     This program is free software; you can redistribute it and/or
##              modify it under the same terms as Perl itself
#############################################################################


{ package AI::NNEasy ;

  
use strict qw(vars) ; no warnings ;

  
use vars qw(%CLASS_HPLOO @ISA $VERSION) ;

  
$VERSION = '0.06' ;

  
@ISA = qw(Class::HPLOO::Base UNIVERSAL) ;

  
my $CLASS = 'AI::NNEasy' ; sub __CLASS__ { 'AI::NNEasy' } ;

  
use Class::HPLOO::Base ;

  use AI::NNEasy::NN ;
  use Storable qw(freeze thaw) ;
  use Data::Dumper ;
  


  sub NNEasy { 
    my $this = ref($_[0]) ? shift : undef ;
    my $CLASS = ref($this) || __PACKAGE__ ;
    my $file = shift(@_) ;
    my @out_types = ref($_[0]) eq 'ARRAY' ? @{ shift(@_) } : ( ref($_[0]) eq 'HASH' ? %{ shift(@_) } : shift(@_) ) ;
    my $error_ok = shift(@_) ;
    my $in = shift(@_) ;
    my $out = shift(@_) ;
    my @layers = ref($_[0]) eq 'ARRAY' ? @{ shift(@_) } : ( ref($_[0]) eq 'HASH' ? %{ shift(@_) } : shift(@_) ) ;
    my $conf = shift(@_) ;
    
    $file ||= 'nneasy.nne' ;
  
    if ( $this->load($file) ) {
      return $this ;
    }
  
    my $in_sz  = ref $in  ? $in->{nodes}  : $in ;
    my $out_sz = ref $out ? $out->{nodes} : $out ;
  
    @layers = ($in_sz+$out_sz) if !@layers ;
    
    foreach my $layers_i ( @layers ) {
      $layers_i = $in_sz+$out_sz if $layers_i <= 0 ;
    }
    
    $conf ||= {} ;
    
    my $decay = $$conf{decay} || 0 ; 
    
    my $nn_in  = $this->_layer_conf( { decay=>$decay } , $in ) ;
    my $nn_out  = $this->_layer_conf( { decay=>$decay , activation_function=>'linear' } , $out ) ;
    
    foreach my $layers_i ( @layers ) {
      $layers_i = $this->_layer_conf( { decay=>$decay } , $layers_i ) ;
    }
    
    my $nn_conf = {random_connections=>0 , networktype=>'feedforward' , random_weights=>1 , learning_algorithm=>'backprop' , learning_rate=>0.1 , bias=>1} ;
    foreach my $Key ( keys %$nn_conf ) { $$nn_conf{$Key} = $$conf{$Key} if exists $$conf{$Key} ;}
    
    $this->{NN_ARGS} = [[ $nn_in , @layers , $nn_out ] , $nn_conf] ;

    $this->{NN} = AI::NNEasy::NN->new( @{$this->{NN_ARGS}} ) ;
    
    $this->{FILE} = $file ;
    
    @out_types = (0,1) if !@out_types ;
    
    @out_types = sort {$a <=> $b} @out_types ;
    
    $this->{OUT_TYPES} = \@out_types ;
    
    if ( $error_ok <= 0 ) {
      my ($min_dif , $last) ;
      my $i = -1 ;
      foreach my $out_types_i ( @out_types ) {
        ++$i ;
        if ($i > 0) {
          my $dif = $out_types_i - $last ;
          $min_dif = $dif if !defined $min_dif || $dif < $min_dif ;
        }
        $last = $out_types_i ;
      }
      $error_ok = $min_dif / 2 ;
      $error_ok -= $error_ok*0.1 ;
    }
    
    $this->{ERROR_OK} = $error_ok ;
    
    return $this ;
  }
  
  sub _layer_conf { 
    my $this = ref($_[0]) ? shift : undef ;
    my $CLASS = ref($this) || __PACKAGE__ ;
    my $def = shift(@_) ;
    my $conf = shift(@_) ;
    
    $def ||= {} ;
    $conf = { nodes=>$conf } if !ref($conf) ;
    
    foreach my $Key ( keys %$def ) { $$conf{$Key} = $$def{$Key} if !exists $$conf{$Key} ;}
  
    my $layer_conf  = {nodes=>1  , persistent_activation=>0 , decay=>0 , random_activation=>0 , threshold=>0 , activation_function=>'tanh' , random_weights=>1} ;
    foreach my $Key ( keys %$layer_conf ) { $$layer_conf{$Key} = $$conf{$Key} if exists $$conf{$Key} ;}

    return $layer_conf ;
  }
  
  sub reset_nn { 
    my $this = ref($_[0]) ? shift : undef ;
    my $CLASS = ref($this) || __PACKAGE__ ;
    
    $this->{NN} = AI::NNEasy::NN->new( @{ $this->{NN_ARGS} } ) ;
  }
  
  sub load { 
    my $this = ref($_[0]) ? shift : undef ;
    my $CLASS = ref($this) || __PACKAGE__ ;
    my $file = shift(@_) ;
    
    $file ||= $this->{FILE} ;
    if ( -s $file ) {
      open (my $fh, $file) ;
      my $dump = join '' , <$fh> ;
      close ($fh) ;
      
      my $restored = thaw($dump) ;
      
      if ($restored) {
        my $fl = $this->{FILE} ;
        %$this = %$restored ;
        $this->{FILE} = $fl if $fl ;
        return 1 ;
      }
    }
    return ;
  }
  
  sub save { 
    my $this = ref($_[0]) ? shift : undef ;
    my $CLASS = ref($this) || __PACKAGE__ ;
    my $file = shift(@_) ;
    
    $file ||= $this->{FILE} ;
        
    my $dump = freeze( {%$this} ) ;
    open (my $fh,">$this->{FILE}") ;
    print $fh $dump ;
    close ($fh) ;
  }
  
  sub learn { 
    my $this = ref($_[0]) ? shift : undef ;
    my $CLASS = ref($this) || __PACKAGE__ ;
    my $in = shift(@_) ;
    my $out = shift(@_) ;
    my $n = shift(@_) ;
    
    $n ||= 100 ;
    
    my $err ;
    for (1..100) {
      $this->{NN}->run($in) ;
      $err = $this->{NN}->learn($out) ;
    }
    
    $err *= -1 if $err < 0 ;
    return $err ;
  }
  
  *_learn_set_get_output_error = \&_learn_set_get_output_error_c ;
  
  sub _learn_set_get_output_error_pl { 
    my $this = ref($_[0]) ? shift : undef ;
    my $CLASS = ref($this) || __PACKAGE__ ;
    my $set = shift(@_) ;
    my $error_ok = shift(@_) ;
    my $ins_ok = shift(@_) ;
    my $verbose = shift(@_) ;
    
    for (my $i = 0 ; $i < @$set ; $i+=2) {
      $this->{NN}->run($$set[$i]) ;
      $this->{NN}->learn($$set[$i+1]) ;
    }

    my ($err,$learn_ok,$print) ;
    for (my $i = 0 ; $i < @$set ; $i+=2) {
      $this->{NN}->run($$set[$i]) ;
      my $er = $this->{NN}->RMSErr($$set[$i+1]) ;
      $er *= -1 if $er < 0 ;
      ++$learn_ok if $er < $error_ok ;
      $err += $er ;
      $print .= join(' ',@{$$set[$i]}) ." => ". join(' ',@{$$set[$i+1]}) ." > $er\n" if $verbose ;
    }
    
    $err /= $ins_ok ;
    
    return ( $err , $learn_ok , $print ) ;
  }
  
  
  
  
    
  sub learn_set { 
    my $this = ref($_[0]) ? shift : undef ;
    my $CLASS = ref($this) || __PACKAGE__ ;
    my @set = ref($_[0]) eq 'ARRAY' ? @{ shift(@_) } : ( ref($_[0]) eq 'HASH' ? %{ shift(@_) } : shift(@_) ) ;
    my $ins_ok = shift(@_) ;
    my $limit = shift(@_) ;
    my $verbose = shift(@_) ;
    
    my $ins_sz = @set / 2 ;

    $ins_ok ||= $ins_sz ;
    
    my $err_static_limit = 15 ;
    my $err_static_limit_positive ;

    if ( ref($limit) eq 'ARRAY' ) {
      ($limit,$err_static_limit,$err_static_limit_positive) = @$limit ;
    }
    
    $limit ||= 30000 ;
    $err_static_limit_positive ||= $err_static_limit/2 ;
  
    my $error_ok = $this->{ERROR_OK} ;
    
    my $check_diff_count = 1000 ;
    
    my ($learn_ok,$counter,$err,$err_last,$err_count,$err_static, $reset_count1 , $reset_count2 ,$print) ;
    
    $err_static = 0 ;
    
    while ( ($learn_ok < $ins_ok) && ($counter < $limit) ) {
      ($err , $learn_ok , $print) = $this->_learn_set_get_output_error(\@set , $error_ok , $ins_ok , $verbose) ;
      
      ++$counter ;
      
      if ( !($counter % 100) || $learn_ok == $ins_ok ) {
        my $err_diff = $err_last - $err ;
        $err_diff *= -1 if $err_diff < 0 ;
        
        $err_count += $err_diff ;
        
        ++$err_static if $err_diff <= 0.00001 || $err > 1 ;
        
        print "err_static = $err_static\n" if $verbose && $err_static ;

        $err_last = $err ;
        
        my $reseted ;
        if ( $err_static >= $err_static_limit || ($err > 1 && $err_static >= $err_static_limit_positive) ) {
          $err_static = 0 ;
          $counter -= 2000 ;
          $reseted = 1 ;
          ++$reset_count1 ;
          
          if ( ( $reset_count1 + $reset_count2 ) > 2 ) {
            $reset_count1 = $reset_count2 = 0 ;
            print "** Reseting NN...\n" if $verbose ;
            $this->reset_nn ;
          }
          else {
            print "** Reseting weights due NULL diff...\n" if $verbose ;
            $this->{NN}->init ;
          }
        }
        
        if ( !($counter % $check_diff_count) ) {
          $err_count /= ($check_diff_count/100) ;
          
          print "ERR COUNT> $err_count\n" if $verbose ;
          
          if ( !$reseted && $err_count < 0.001 ) {
            $err_static = 0 ;
            $counter -= 1000 ;
            ++$reset_count2 ;
            
            if ( ($reset_count1 + $reset_count2) > 2 ) {
              $reset_count1 = $reset_count2 = 0 ;
              print "** Reseting NN...\n" if $verbose ;
              $this->reset_nn ;
            }
            else {
              print "** Reseting weights due LOW diff...\n" if $verbose ;
              $this->{NN}->init ;
            }
          }

          $err_count = 0 ;
        }
        
        if ( $verbose ) {
          print "\nepoch $counter : error_ok = $error_ok : error = $err : err_diff = $err_diff : err_static = $err_static : ok = $learn_ok\n" ;
          print $print ;
        }
      }

      print "epoch $counter : error = $err : ok = $learn_ok\n" if $verbose > 1 ;
      
    }
    
  }
  
  sub get_set_error { 
    my $this = ref($_[0]) ? shift : undef ;
    my $CLASS = ref($this) || __PACKAGE__ ;
    my @set = ref($_[0]) eq 'ARRAY' ? @{ shift(@_) } : ( ref($_[0]) eq 'HASH' ? %{ shift(@_) } : shift(@_) ) ;
    my $ins_ok = shift(@_) ;
    
    my $ins_sz = @set / 2 ;

    $ins_ok ||= $ins_sz ;
  
    my $err ;
    for (my $i = 0 ; $i < @set ; $i+=2) {
      $this->{NN}->run($set[$i]) ;
      my $er = $this->{NN}->RMSErr($set[$i+1]) ;
      $er *= -1 if $er < 0 ;
      $err += $er ;
    }
    
    $err /= $ins_ok ;
    return $err ;
  }
  
  sub run { 
    my $this = ref($_[0]) ? shift : undef ;
    my $CLASS = ref($this) || __PACKAGE__ ;
    my $in = shift(@_) ;
    
    $this->{NN}->run($in) ;
    my $out = $this->{NN}->output() ;
    return $out ;
  }
  
  sub run_get_winner { 
    my $this = ref($_[0]) ? shift : undef ;
    my $CLASS = ref($this) || __PACKAGE__ ;
    
    my $out = $this->run(@_) ;
    
    foreach my $out_i ( @$out ) {
      $out_i = $this->out_type_winner($out_i) ;
    }
    
    return $out ;
  }
  
  sub out_type_winner { 
    my $this = ref($_[0]) ? shift : undef ;
    my $CLASS = ref($this) || __PACKAGE__ ;
    my $val = shift(@_) ;
    
    my ($out_type , %err) ;
    
    foreach my $types_i ( @{ $this->{OUT_TYPES} } ) {
      my $er = $types_i - $val ;
      $er *= -1 if $er < 0 ;
      $err{$types_i} = $er ;
    }
    
    my $min_type_err = (sort { $err{$a} <=> $err{$b} } keys %err)[0] ;
    $out_type = $min_type_err ;

    return $out_type ;
  }


my $INLINE_INSTALL ; BEGIN { use Config ; my @installs = ($Config{installarchlib} , $Config{installprivlib} , $Config{installsitelib}) ; foreach my $i ( @installs ) { $i =~ s/[\\\/]/\//gs ;} $INLINE_INSTALL = 1 if ( __FILE__ =~ /\.pm$/ && ( join(" ",...

use Inline C => <<'__INLINE_C_SRC__' , ( $INLINE_INSTALL ? (NAME => 'AI::NNEasy' , VERSION => '0.06') : () ) ;


#define OBJ_SV(self)		SvRV( self )
#define OBJ_HV(self)		(HV*) SvRV( self )
#define OBJ_AV(self)		(AV*) SvRV( self )

#define FETCH_ATTR(hv,k)	*hv_fetch(hv, k , strlen(k) , 0)
#define FETCH_ATTR_PV(hv,k)	SvPV( FETCH_ATTR(hv,k) , len)
#define FETCH_ATTR_NV(hv,k)	SvNV( FETCH_ATTR(hv,k) )
#define FETCH_ATTR_IV(hv,k)	SvIV( FETCH_ATTR(hv,k) )  
#define FETCH_ATTR_HV(hv,k)	(HV*) FETCH_ATTR(hv,k)
#define FETCH_ATTR_AV(hv,k)	(AV*) FETCH_ATTR(hv,k)
#define FETCH_ATTR_SV_REF(hv,k)	SvRV( FETCH_ATTR(hv,k) )
#define FETCH_ATTR_HV_REF(hv,k)	(HV*) SvRV( FETCH_ATTR(hv,k) )
#define FETCH_ATTR_AV_REF(hv,k)	(AV*) SvRV( FETCH_ATTR(hv,k) )

#define FETCH_ELEM(av,i)		*av_fetch(av,i,0)
#define FETCH_ELEM_HV_REF(av,i)	(HV*) SvRV( FETCH_ELEM(av,i) )
#define FETCH_ELEM_AV_REF(av,i)	(AV*) SvRV( FETCH_ELEM(av,i) )

SV* _av_join( AV* av ) {
    SV* ret = sv_2mortal(newSVpv("",0)) ;
    int i ;
    for (i = 0 ; i <= av_len(av) ; ++i) {
      SV* elem = *av_fetch(av, i ,0) ;
      if (i > 0) sv_catpv(ret , " ") ;
      sv_catsv(ret , elem) ;
    }
    return ret ;
}

void _learn_set_get_output_error_c( SV* self , SV* set , double error_ok , int ins_ok , bool verbose ) {
    dXSARGS;
    
    STRLEN len;
    int i ;
    HV* self_hv = OBJ_HV( self );
    AV* set_av = OBJ_AV( set ) ;

lib/AI/NNEasy.pm  view on Meta::CPAN


=item VERBOSE

If TRUE turn verbose method ON when learning.

=back

=head2 get_set_error (@SET , OK_OUTPUTS)

Get the actual error of a set in the NN. If the returned error is bigger than
I<ERROR_OK> defined on I<new()> you should learn or relearn the set.

=head2 run (@INPUT)

Run a input and return the output calculated by the NN based in what the NN already have learned.

=head2 run_get_winner (@INPUT)

Same of I<run()>, but the output will return the nearest output value based in the
I<@OUTPUT_TYPES> defined at I<new()>.

For example an input I<[0,1]> learned that have
the output I<[1]>, actually will return something like 0.98324 as output and
not 1, since the error never should be 0. So, with I<run_get_winner()>
we get the output of I<run()>, let's say that is 0.98324, and find what output
is near of this number, that in this case should be 1. An output [0], will return
by I<run()> something like 0.078964, and I<run_get_winner()> return 0.

=head1 Samples

Inside the release sources you can find the directory ./samples where you have some
examples of code using this module.

=head1 INLINE C

Some functions of this module have I<Inline> functions writed in C.

I have made a C version only for the functions that are wild called, like:

  AI::NNEasy::_learn_set_get_output_error

  AI::NNEasy::NN::tanh

  AI::NNEasy::NN::feedforward::run
  
  AI::NNEasy::NN::backprop::hiddenToOutput
  AI::NNEasy::NN::backprop::hiddenOrInputToHidden
  AI::NNEasy::NN::backprop::RMSErr

What give to us the speed that we need to learn fast the inputs, but at the same time
be able to create flexible NN.

=head1 Class::HPLOO

I have used L<Class::HPLOO> to write fast the module, specially the XS support.

L<Class::HPLOO> enables this kind of syntax for Perl classes:

  class Foo {
    
    sub bar($x , $y) {
      $this->add($x , $y) ;
    }
    
    sub[C] int add( int x , int y ) {
      int res = x + y ;
      return res ;
    }
    
  }

What make possible to write the module in 2 days! ;-P

=head1 Basics of a Neural Network

I<- This is just a simple text for lay pleople,
to try to make them to understand what is a Neural Network and how it works
without need to read a lot of books -.>

A NN is based in nodes/neurons and layers, where we have the input layer, the hidden layers and the output layer.

For example, here we have a NN with 2 inputs, 1 hidden layer, and 2 outputs:

         Input  Hidden  Output
 input1  ---->n1\    /---->n4---> output1
                 \  /
                  n3
                 /  \
 input2  ---->n2/    \---->n5---> output2


Basically, when we have an input, let's say [0,1], it will active I<n2>, that will
active I<n3> and I<n3> will active I<n4> and I<n5>, but the link between I<n3> and I<n4> has a I<weight>, and
between I<n3> and I<n5> another I<weight>. The idea is to find the I<weights> between the
nodes that can give to us an output near the real output. So, if the output of [0,1]
is [1,1], the nodes I<output1> and I<output2> should give to us a number near 1,
let's say 0.98654. And if the output for [0,0] is [0,0], I<output1> and I<output2> should give to us a number near 0,
let's say 0.078875.

What is hard in a NN is to find this I<weights>. By default L<AI::NNEasy> uses
I<backprop> as learning algorithm. With I<backprop> it pastes the inputs through
the Neural Network and adjust the I<weights> using random numbers until we find
a set of I<weights> that give to us the right output.

The secret of a NN is the number of hidden layers and nodes/neurons for each layer.
Basically the best way to define the hidden layers is 1 layer of (INPUT_NODES+OUTPUT_NODES).
So, a layer of 2 input nodes and 1 output node, should have 3 nodes in the hidden layer.
This definition exists because the number of inputs define the maximal variability of
the inputs (N**2 for bollean inputs), and the output defines if the variability is reduced by some logic restriction, like
int the XOR example, where we have 2 inputs and 1 output, so, hidden is 3. And as we can see in the
logic we have 3 groups of inputs:

  0 0 => 0 # false
  0 1 => 1 # or
  1 0 => 1 # or
  1 1 => 1 # true

Actually this is not the real explanation, but is the easiest way to understand that
you need to have a number of nodes/neuros in the hidden layer that can give the
right output for your problem.



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