
    hx$                         S r SSKrSSKJr  SSKJr  SSKJr  SS/r	\R                  " SS	9SS
 j5       r\R                  " SS	9 SS j5       rS rS rSS jrSS jrg)z5Betweenness centrality measures for subsets of nodes.    N)_add_edge_keys)"_single_source_dijkstra_path_basic)"_single_source_shortest_path_basicbetweenness_centrality_subset"edge_betweenness_centrality_subsetweight)
edge_attrsc           	          [         R                  U S5      nU H1  nUc  [        X5      u  pxpO[        XU5      u  pxp[	        XWXXb5      nM3     [        U[        U 5      X0R                  5       S9nU$ )a$  Compute betweenness centrality for a subset of nodes.

.. math::

   c_B(v) =\sum_{s\in S, t \in T} \frac{\sigma(s, t|v)}{\sigma(s, t)}

where $S$ is the set of sources, $T$ is the set of targets,
$\sigma(s, t)$ is the number of shortest $(s, t)$-paths,
and $\sigma(s, t|v)$ is the number of those paths
passing through some  node $v$ other than $s, t$.
If $s = t$, $\sigma(s, t) = 1$,
and if $v \in {s, t}$, $\sigma(s, t|v) = 0$ [2]_.


Parameters
----------
G : graph
  A NetworkX graph.

sources: list of nodes
  Nodes to use as sources for shortest paths in betweenness

targets: list of nodes
  Nodes to use as targets for shortest paths in betweenness

normalized : bool, optional
  If True the betweenness values are normalized by $2/((n-1)(n-2))$
  for graphs, and $1/((n-1)(n-2))$ for directed graphs where $n$
  is the number of nodes in G.

weight : None or string, optional (default=None)
  If None, all edge weights are considered equal.
  Otherwise holds the name of the edge attribute used as weight.
  Weights are used to calculate weighted shortest paths, so they are
  interpreted as distances.

Returns
-------
nodes : dictionary
   Dictionary of nodes with betweenness centrality as the value.

See Also
--------
edge_betweenness_centrality
load_centrality

Notes
-----
The basic algorithm is from [1]_.

For weighted graphs the edge weights must be greater than zero.
Zero edge weights can produce an infinite number of equal length
paths between pairs of nodes.

The normalization might seem a little strange but it is
designed to make betweenness_centrality(G) be the same as
betweenness_centrality_subset(G,sources=G.nodes(),targets=G.nodes()).

The total number of paths between source and target is counted
differently for directed and undirected graphs. Directed paths
are easy to count. Undirected paths are tricky: should a path
from "u" to "v" count as 1 undirected path or as 2 directed paths?

For betweenness_centrality we report the number of undirected
paths when G is undirected.

For betweenness_centrality_subset the reporting is different.
If the source and target subsets are the same, then we want
to count undirected paths. But if the source and target subsets
differ -- for example, if sources is {0} and targets is {1},
then we are only counting the paths in one direction. They are
undirected paths but we are counting them in a directed way.
To count them as undirected paths, each should count as half a path.

References
----------
.. [1] Ulrik Brandes, A Faster Algorithm for Betweenness Centrality.
   Journal of Mathematical Sociology 25(2):163-177, 2001.
   https://doi.org/10.1080/0022250X.2001.9990249
.. [2] Ulrik Brandes: On Variants of Shortest-Path Betweenness
   Centrality and their Generic Computation.
   Social Networks 30(2):136-145, 2008.
   https://doi.org/10.1016/j.socnet.2007.11.001
        
normalizeddirected)dictfromkeysshortest_pathdijkstra_accumulate_subset_rescalelenis_directed)Gsourcestargetsr   r   bsSPsigma_s              c/var/www/html/env/lib/python3.13/site-packages/networkx/algorithms/centrality/betweenness_subset.pyr   r      sq    l 	aA>*10NA%%aF3NA%qQq:  	CFzMMOLAH    c           	         [         R                  U S5      nUR                  [         R                  U R                  5       S5      5        U H1  nUc  [	        X5      u  pxpO[        XU5      u  pxp[        XWXXb5      nM3     U  H  nX[	 M     [        U[        U 5      X0R                  5       S9nU R                  5       (       a
  [        XUS9nU$ )a  Compute betweenness centrality for edges for a subset of nodes.

.. math::

   c_B(v) =\sum_{s\in S,t \in T} \frac{\sigma(s, t|e)}{\sigma(s, t)}

where $S$ is the set of sources, $T$ is the set of targets,
$\sigma(s, t)$ is the number of shortest $(s, t)$-paths,
and $\sigma(s, t|e)$ is the number of those paths
passing through edge $e$ [2]_.

Parameters
----------
G : graph
  A networkx graph.

sources: list of nodes
  Nodes to use as sources for shortest paths in betweenness

targets: list of nodes
  Nodes to use as targets for shortest paths in betweenness

normalized : bool, optional
  If True the betweenness values are normalized by `2/(n(n-1))`
  for graphs, and `1/(n(n-1))` for directed graphs where `n`
  is the number of nodes in G.

weight : None or string, optional (default=None)
  If None, all edge weights are considered equal.
  Otherwise holds the name of the edge attribute used as weight.
  Weights are used to calculate weighted shortest paths, so they are
  interpreted as distances.

Returns
-------
edges : dictionary
   Dictionary of edges with Betweenness centrality as the value.

See Also
--------
betweenness_centrality
edge_load

Notes
-----
The basic algorithm is from [1]_.

For weighted graphs the edge weights must be greater than zero.
Zero edge weights can produce an infinite number of equal length
paths between pairs of nodes.

The normalization might seem a little strange but it is the same
as in edge_betweenness_centrality() and is designed to make
edge_betweenness_centrality(G) be the same as
edge_betweenness_centrality_subset(G,sources=G.nodes(),targets=G.nodes()).

References
----------
.. [1] Ulrik Brandes, A Faster Algorithm for Betweenness Centrality.
   Journal of Mathematical Sociology 25(2):163-177, 2001.
   https://doi.org/10.1080/0022250X.2001.9990249
.. [2] Ulrik Brandes: On Variants of Shortest-Path Betweenness
   Centrality and their Generic Computation.
   Social Networks 30(2):136-145, 2008.
   https://doi.org/10.1016/j.socnet.2007.11.001
r   r   )r   )r   r   updateedgesr   r   _accumulate_edges_subset
_rescale_er   r   is_multigraphr   )r   r   r   r   r   r   r   r   r   r   r   ns               r    r   r   v   s    L 	aAHHT]]1779c*+>*10NA%%aF3NA%$Q1Q@  D 1c!fmmoNA1/Hr!   c                 $   [         R                  US5      n[        U5      U1-
  nU(       ac  UR                  5       nX;   a  Xh   S-   X8   -  n	O	Xh   X8   -  n	X(    H  n
Xj==   X:   U	-  -  ss'   M     X:w  a  X==   Xh   -  ss'   U(       a  Mc  U $ )Nr         ?)r   r   setpop)betweennessr   r   r   r   r   delta
target_setwcoeffvs              r    r   r      s    MM!S!EW#J
EEG?X^ux/EHux'EAH5((H 6Neh&N ! r!   c                 v   [         R                  US5      n[        U5      nU(       a  UR                  5       nX(    H\  n	X;   a  X9   X8   -  SXh   -   -  n
OXh   [	        X(   5      -  n
X4U ;  a  XU	4==   U
-  ss'   OX	U4==   U
-  ss'   Xi==   U
-  ss'   M^     X:w  a  X==   Xh   -  ss'   U(       a  M  U $ )*edge_betweenness_centrality_subset helper.r   r*   )r   r   r+   r,   r   )r-   r   r   r   r   r   r.   r/   r0   r2   cs              r    r%   r%      s    MM!QEWJ
EEGAX(S58^<Hs14y(v[(F#q(#F#q(#HMH  6Neh&N ! r!   c                     U(       a  US::  a  SnOSUS-
  US-
  -  -  nOU(       d  SnOSnUb  U  H  nX==   U-  ss'   M     U $ )z%betweenness_centrality_subset helper.   Nr*            ? r-   r(   r   r   scaler2   s         r    r   r      sW    6EAEa!e,-EEEANe#N r!   c                     U(       a  US::  a  SnOSXS-
  -  -  nOU(       d  SnOSnUb  U  H  nX==   U-  ss'   M     U $ )r4   r8   Nr*   r9   r:   r;   s         r    r&   r&     sP    6E1A;'EEEANe#N r!   )FN)F)__doc__networkxnx*networkx.algorithms.centrality.betweennessr   r   r   r   r   __all___dispatchabler   r   r   r%   r   r&   r:   r!   r    <module>rD      s    ; 
 $( X&^ '^B X&26S 'Sl *$r!   