Class: FpGrowth::FpTreeNode

Inherits:
Object
  • Object
show all
Defined in:
lib/fp_growth/fp_tree_node.rb

Overview

knows nothing about header list

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(key, count = 1) ⇒ FpTreeNode

Returns a new instance of FpTreeNode.



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# File 'lib/fp_growth/fp_tree_node.rb', line 11

def initialize(key, count = 1)
  @key = key
  @count = count
  @parent = nil
  @children = []
end

Instance Attribute Details

#children ⇒ Object (readonly)

Returns the value of attribute children.



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# File 'lib/fp_growth/fp_tree_node.rb', line 6

def children
  @children
end

#count ⇒ Object (readonly)

Returns the value of attribute count.



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# File 'lib/fp_growth/fp_tree_node.rb', line 6

def count
  @count
end

#key ⇒ Object (readonly)

Returns the value of attribute key.



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# File 'lib/fp_growth/fp_tree_node.rb', line 6

def key
  @key
end

#parent ⇒ Object

Returns the value of attribute parent.



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# File 'lib/fp_growth/fp_tree_node.rb', line 7

def parent
  @parent
end

Instance Method Details

#add_child(child) ⇒ Object 



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# File 'lib/fp_growth/fp_tree_node.rb', line 18

def add_child(child)
  @children << child
  child.parent = self
end

#clone_children(new_parent) ⇒ Object 



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# File 'lib/fp_growth/fp_tree_node.rb', line 53

def clone_children(new_parent)
  @children.each do |child|
    cloned_child = child.clone
    cloned_child.parent = new_parent
    new_parent.children << cloned_child
  end
end

#each(&block) ⇒ Object

walks recursive through whole tree, without self



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# File 'lib/fp_growth/fp_tree_node.rb', line 62

def each &block
  children.each do |child|
    block.call(child)
    child.each(&block)
  end
end

#find_child(key) ⇒ Object 



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# File 'lib/fp_growth/fp_tree_node.rb', line 23

def find_child(key)
  children.find { |child| child.key == key }
end

#increase_count(value = 1) ⇒ Object 



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# File 'lib/fp_growth/fp_tree_node.rb', line 39

def increase_count(value = 1)
  @count += value
end

#is_root? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/fp_growth/fp_tree_node.rb', line 69

def is_root?
  !parent
end

#prefix_path ⇒ Object 



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# File 'lib/fp_growth/fp_tree_node.rb', line 43

def prefix_path
  result = FpGrowth::PrefixPath.new(count)
  node = parent
  while !node.is_root?
    result << node.key
    node = node.parent
  end
  result
end

#to_s(depth = 0) ⇒ Object

prints tree structure



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# File 'lib/fp_growth/fp_tree_node.rb', line 28

def to_s(depth = 0)
  if false
    title = @key ? "#{@key}:#{count}" : 'root'
    "( #{title} #{@children.collect { |child| child.to_s }.join(' ')})"
  else
    result = key ? "#{@key}:#{count} " : ''
    result << @children.collect { |child| child.to_s(depth + 1) }.join("\n" << ' ' * 4 * depth)
    result
  end
end