Class: Newral::Genetic::Tree

Inherits:
Object
  • Object
show all
Defined in:
lib/newral/genetic/tree.rb

Constant Summary collapse

OPERANDS = 
{ 
  '+' => 2,
  '*' => 2,
  '/' => 2,
  '-' => 2,
  'pow' => 2, 
  'sqrt' => 1
}

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(parent: nil, value: nil, right_child: nil, left_child: nil) ⇒ Tree

Returns a new instance of Tree.



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# File 'lib/newral/genetic/tree.rb', line 14

def initialize( parent: nil, value:nil, right_child: nil, left_child: nil )
  @parent = parent
  @left_child = left_child
  @right_child = right_child
  update_node_count
  @value = value
end

Instance Attribute Details

#left_child ⇒ Object (readonly)

Returns the value of attribute left_child.



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# File 'lib/newral/genetic/tree.rb', line 4

def left_child
  @left_child
end

#parent ⇒ Object

Returns the value of attribute parent.



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# File 'lib/newral/genetic/tree.rb', line 5

def parent
  @parent
end

#right_child ⇒ Object (readonly)

Returns the value of attribute right_child.



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# File 'lib/newral/genetic/tree.rb', line 4

def right_child
  @right_child
end

#sub_node_count ⇒ Object (readonly)

Returns the value of attribute sub_node_count.



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# File 'lib/newral/genetic/tree.rb', line 4

def sub_node_count
  @sub_node_count
end

#value ⇒ Object (readonly)

Returns the value of attribute value.



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# File 'lib/newral/genetic/tree.rb', line 4

def value
  @value
end

Class Method Details

.full_tree(depth: 3, allowed_operands: OPERANDS.keys, terminal_nodes: []) ⇒ Object 



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# File 'lib/newral/genetic/tree.rb', line 54

def self.full_tree( depth:3, allowed_operands: OPERANDS.keys, terminal_nodes:[]  )
  if depth > 1
    value =  allowed_operands[ rand(allowed_operands.size) ]
    tree = Tree.new( value: value )
    tree.set_child_trees( left_child: Tree.full_tree( depth: depth-1, allowed_operands: allowed_operands, terminal_nodes: terminal_nodes ))
    if OPERANDS[value] == 2 
      tree.set_child_trees( right_child: Tree.full_tree( depth: depth-1, allowed_operands: allowed_operands, terminal_nodes: terminal_nodes ))
    end
    tree
  else 
    Tree.new( value: terminal_nodes[rand(terminal_nodes.size)])
  end
end

Instance Method Details

#eval ⇒ Object 



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# File 'lib/newral/genetic/tree.rb', line 41

def eval
  case @value 
    when '+' then @left_child.eval+@right_child.eval
    when '-' then @left_child.eval-@right_child.eval
    when '*' then @left_child.eval*@right_child.eval
    when '/' then @left_child.eval/@right_child.eval
    when 'pow' then @left_child.eval**@right_child.eval
    when 'sqrt' then @left_child.eval**0.5
  else 
    @value
  end
end

#node_count ⇒ Object 



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# File 'lib/newral/genetic/tree.rb', line 28

def node_count 
  @sub_node_count+1
end

#set_child_trees(left_child: nil, right_child: nil, force: false) ⇒ Object 



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# File 'lib/newral/genetic/tree.rb', line 32

def set_child_trees( left_child: nil, right_child: nil, force: false )
  @left_child = left_child if left_child || force
  @right_child = right_child if right_child || force
  @right_child.parent = self if @right_child
  @left_child.parent = self if @left_child
  update_node_count
  self
end

#update_node_count ⇒ Object 



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# File 'lib/newral/genetic/tree.rb', line 22

def update_node_count 
  @sub_node_count = ( @left_child && 1 ).to_i+( @left_child && @left_child.sub_node_count ).to_i+( @right_child && 1 ).to_i+( @right_child && @right_child.sub_node_count ).to_i
  @parent.update_node_count if @parent
  @sub_node_count
end