Module: Tree::Utils::TreeMetricsHandler

Included in:
TreeNode
Defined in:
lib/tree/utils/metrics_methods.rb

Overview

Provides utility functions to measure various tree metrics.

Metrics and Measures collapse

Instance Attribute Details

#breadth ⇒ Integer (readonly)

Breadth of the tree at this node’s level. A single node without siblings has a breadth of 1.

Breadth is defined to be:

Breadth

Number of sibling nodes to this node + 1 (this node itself),

i.e., the number of children the parent of this node has.

Returns:

  • (Integer) —

    breadth of the node’s level.



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# File 'lib/tree/utils/metrics_methods.rb', line 117

def breadth
  root? ? 1 : parent.children.size
end

#in_degree ⇒ Integer (readonly)

The incoming edge-count of this node.

In-degree is defined as:

In-degree

Number of edges arriving at the node (0 for root, 1 for

all other nodes)

  • In-degree = 0 for a root or orphaned node

  • In-degree = 1 for a node which has a parent

Returns:

  • (Integer) —

    The in-degree of this node.



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# File 'lib/tree/utils/metrics_methods.rb', line 132

def in_degree
  root? ? 0 : 1
end

#length ⇒ Integer (readonly)

Deprecated.

This method name is ambiguous and may be removed. Use

Convenience synonym for #size.

#size instead.

Returns:

  • (Integer) —

    The total number of nodes in this (sub)tree.

See Also:



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# File 'lib/tree/utils/metrics_methods.rb', line 66

def length
  size
end

#level ⇒ Object (readonly)

Alias for #node_depth

See Also:



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# File 'lib/tree/utils/metrics_methods.rb', line 104

def level
  node_depth
end

#node_depth ⇒ Integer (readonly)

Depth of this node in its tree. Depth of a node is defined as:

Depth

Length of the node’s path to its root. Depth of a root node is

zero.

#level is an alias for this method.

Returns:

  • (Integer) —

    Depth of this node.



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# File 'lib/tree/utils/metrics_methods.rb', line 94

def node_depth
  return 0 if root?

  1 + parent.node_depth
end

#node_height ⇒ Integer (readonly)

Height of the (sub)tree from this node. Height of a node is defined as:

Height

Length of the longest downward path to a leaf from the node.

  • Height from a root node is height of the entire tree.

  • The height of a leaf node is zero.

Returns:

  • (Integer) —

    Height of the node.



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# File 'lib/tree/utils/metrics_methods.rb', line 79

def node_height
  return 0 if leaf?

  1 + @children.collect(&:node_height).max
end

#out_degree ⇒ Integer (readonly)

The outgoing edge-count of this node.

Out-degree is defined as:

Out-degree

Number of edges leaving the node (zero for leafs)

Returns:

  • (Integer) —

    The out-degree of this node.



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# File 'lib/tree/utils/metrics_methods.rb', line 143

def out_degree
  leaf? ? 0 : children.size
end

#size ⇒ Integer (readonly)

Total number of nodes in this (sub)tree, including this node.

Size of the tree is defined as:

Size

Total number nodes in the subtree including this node.

Returns:

  • (Integer) —

    Total number of nodes in this (sub)tree.



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# File 'lib/tree/utils/metrics_methods.rb', line 54

def size
  inject(0) { |sum, node| sum + 1 if node }
end