
    \Mh                         d Z ddlZddlmZ ddlmZ g dZ ed          ej        d                         Z	 ed          ej        d	                         Z
 ed          ej        d
                         ZdS )zDProvides functions for computing the efficiency of nodes and graphs.    N)NetworkXNoPath   )not_implemented_for)
efficiencylocal_efficiencyglobal_efficiencydirectedc                 `    	 dt          j        | ||          z  }n# t          $ r d}Y nw xY w|S )ad  Returns the efficiency of a pair of nodes in a graph.

    The *efficiency* of a pair of nodes is the multiplicative inverse of the
    shortest path distance between the nodes [1]_. Returns 0 if no path
    between nodes.

    Parameters
    ----------
    G : :class:`networkx.Graph`
        An undirected graph for which to compute the average local efficiency.
    u, v : node
        Nodes in the graph ``G``.

    Returns
    -------
    float
        Multiplicative inverse of the shortest path distance between the nodes.

    Examples
    --------
    >>> G = nx.Graph([(0, 1), (0, 2), (0, 3), (1, 2), (1, 3)])
    >>> nx.efficiency(G, 2, 3)  # this gives efficiency for node 2 and 3
    0.5

    Notes
    -----
    Edge weights are ignored when computing the shortest path distances.

    See also
    --------
    local_efficiency
    global_efficiency

    References
    ----------
    .. [1] Latora, Vito, and Massimo Marchiori.
           "Efficient behavior of small-world networks."
           *Physical Review Letters* 87.19 (2001): 198701.
           <https://doi.org/10.1103/PhysRevLett.87.198701>

       r   )nxshortest_path_lengthr   )Guveffs       g/var/www/html/test/jupyter/venv/lib/python3.11/site-packages/networkx/algorithms/efficiency_measures.pyr   r      sL    X")!Q222   Js    ++c                     t          |           }||dz
  z  }|dk    rLt          j        |           }d}|D ]-\  }}|                                D ]\  }}|dk    r|d|z  z  }.||z  }nd}|S )a3  Returns the average global efficiency of the graph.

    The *efficiency* of a pair of nodes in a graph is the multiplicative
    inverse of the shortest path distance between the nodes. The *average
    global efficiency* of a graph is the average efficiency of all pairs of
    nodes [1]_.

    Parameters
    ----------
    G : :class:`networkx.Graph`
        An undirected graph for which to compute the average global efficiency.

    Returns
    -------
    float
        The average global efficiency of the graph.

    Examples
    --------
    >>> G = nx.Graph([(0, 1), (0, 2), (0, 3), (1, 2), (1, 3)])
    >>> round(nx.global_efficiency(G), 12)
    0.916666666667

    Notes
    -----
    Edge weights are ignored when computing the shortest path distances.

    See also
    --------
    local_efficiency

    References
    ----------
    .. [1] Latora, Vito, and Massimo Marchiori.
           "Efficient behavior of small-world networks."
           *Physical Review Letters* 87.19 (2001): 198701.
           <https://doi.org/10.1103/PhysRevLett.87.198701>

    r   r   )lenr   all_pairs_shortest_path_lengthitems)	r   ndenomlengthsg_effsourcetargetstargetdistances	            r   r   r   >   s    T 	AAQKEzz3A66& 	* 	*OFG$+MMOO * * a<<Q\)E* 	  L    c                 ^      fd D             }t          |          t                     z  S )a  Returns the average local efficiency of the graph.

    The *efficiency* of a pair of nodes in a graph is the multiplicative
    inverse of the shortest path distance between the nodes. The *local
    efficiency* of a node in the graph is the average global efficiency of the
    subgraph induced by the neighbors of the node. The *average local
    efficiency* is the average of the local efficiencies of each node [1]_.

    Parameters
    ----------
    G : :class:`networkx.Graph`
        An undirected graph for which to compute the average local efficiency.

    Returns
    -------
    float
        The average local efficiency of the graph.

    Examples
    --------
    >>> G = nx.Graph([(0, 1), (0, 2), (0, 3), (1, 2), (1, 3)])
    >>> nx.local_efficiency(G)
    0.9166666666666667

    Notes
    -----
    Edge weights are ignored when computing the shortest path distances.

    See also
    --------
    global_efficiency

    References
    ----------
    .. [1] Latora, Vito, and Massimo Marchiori.
           "Efficient behavior of small-world networks."
           *Physical Review Letters* 87.19 (2001): 198701.
           <https://doi.org/10.1103/PhysRevLett.87.198701>

    c              3   h   K   | ],}t                              |                             V  -d S )N)r   subgraph).0r   r   s     r   	<genexpr>z#local_efficiency.<locals>.<genexpr>   s<      FFq(AaD)9)9::FFFFFFr   )sumr   )r   efficiency_lists   ` r   r   r   {   s9    V GFFFAFFFO#a&&((r   )__doc__networkxr   networkx.exceptionr   utilsr   __all___dispatchabler   r   r    r   r   <module>r.      s    J J     - - - - - - ' ' ' ' ' '
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