Class: Treemap::Node

Inherits:
Object
  • Object
show all
Defined in:
lib/treemap/node.rb

Overview

A generic tree node class which is used to represent the data to be treemap’ed. The Layout and Output classes expect an object of this type to perform the treemap calculations on.

Create a simple tree:

root = Treemap::Node.new
root.new_child(:size => 6)
root.new_child(:size => 6)
root.new_child(:size => 4)
root.new_child(:size => 3)
root.new_child(:size => 2)
root.new_child(:size => 2)
root.new_child(:size => 1)

Initialize values:

root = Treemap::Node.new(:label => "All", :size => 100, :color => "#FFCCFF")
child1 = Treemap::Node.new(:label => "Child 1", :size => 50)
child2 = Treemap::Node.new(:label => "Child 2", :size => 50)
root.add_child(child1)
root.add_child(child2)

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(opts = {}) ⇒ Node

Create a new Node. You can initialize the node by passing in a hash with any of the following keys:

  • :size - The size that this node represents. For non-leaf nodes the size must be equal to the sum of the sizes of it’s children. If size is nil then the value will be calculated by recursing the children.

  • :label - The label for this node. Used when displaying. Defaults to “node”

  • :color - The background fill color in hex to render when drawing the square. If the value is a number a color will be calculated. An example string color would be: ##FFFFFF (white)

  • :id - A unique id to assign to this node. Default id will be generated if one is not provided.

  • :object - An object, that this node might contain.



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# File 'lib/treemap/node.rb', line 59

def initialize(opts = {})
    @size = opts[:size]
    @label = opts[:label]
    @color = opts[:color]
    @id = opts[:id]
    @object = opts[:object]
    @children = []

    if(@id.nil?)
        make_id
    end
end

Instance Attribute Details

#bounds ⇒ Object

Returns the value of attribute bounds.



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# File 'lib/treemap/node.rb', line 40

def bounds
  @bounds
end

#children ⇒ Object (readonly)

Returns the value of attribute children.



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# File 'lib/treemap/node.rb', line 41

def children
  @children
end

#color ⇒ Object

Returns the value of attribute color.



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# File 'lib/treemap/node.rb', line 40

def color
  @color
end

#id ⇒ Object

Returns the value of attribute id.



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# File 'lib/treemap/node.rb', line 40

def id
  @id
end

#label ⇒ Object

Returns the value of attribute label.



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# File 'lib/treemap/node.rb', line 40

def label
  @label
end

#object ⇒ Object

Returns the value of attribute object.



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# File 'lib/treemap/node.rb', line 40

def object
  @object
end

#parent ⇒ Object

Returns the value of attribute parent.



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# File 'lib/treemap/node.rb', line 40

def parent
  @parent
end

#size ⇒ Object

Returns the value of attribute size.



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# File 'lib/treemap/node.rb', line 40

def size
  @size
end

Instance Method Details

#add_child(node) ⇒ Object 



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# File 'lib/treemap/node.rb', line 80

def add_child(node)
    # XXX check to see that a node with the same label doesn't already exist.
    #     having 2 nodes with the same label at the same depth 
    #     doesn't seem to make sense
    node.parent = self
    @children.push(node)
end

#depth ⇒ Object

Returns the depth of the node. 0 for root.



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# File 'lib/treemap/node.rb', line 75

def depth
    return 0 if parent.nil?
    1 + self.parent.depth
end

#find ⇒ Object 



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# File 'lib/treemap/node.rb', line 96

def find
    @children.find { |c| yield(c) }
end

#font_size(base_size) ⇒ Object

Unscientific formula to calculate the font size depending on the node’s area



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# File 'lib/treemap/node.rb', line 121

def font_size(base_size)
    (base_size * Math.sqrt(self.bounds.width * self.bounds.height) / 125).to_i
end

#leaf? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/treemap/node.rb', line 130

def leaf?
    return true if @children.nil?
    !(@children.size > 0)
end

#new_child(*args) ⇒ Object

Creates a new node and adds it as a child. See new method.



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# File 'lib/treemap/node.rb', line 91

def new_child(*args)
    node = Treemap::Node.new(*args)
    self.add_child(node)
end

#to_s ⇒ Object 



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# File 'lib/treemap/node.rb', line 100

def to_s
    str = "[:id => " + id + " :label => " + label
    str += " :size => " + size.to_s + " :color => " + color.to_s
    if(not(bounds.nil?))
        str += " :bounds => " + bounds.to_s
    end
    str += "]"
    str
end