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+"""Functions for computing the harmonic centrality of a graph."""
+
+from functools import partial
+
+import networkx as nx
+
+__all__ = ["harmonic_centrality"]
+
+
+@nx._dispatchable(edge_attrs="distance")
+def harmonic_centrality(G, nbunch=None, distance=None, sources=None):
+    r"""Compute harmonic centrality for nodes.
+
+    Harmonic centrality [1]_ of a node `u` is the sum of the reciprocal
+    of the shortest path distances from all other nodes to `u`
+
+    .. math::
+
+        C(u) = \sum_{v \neq u} \frac{1}{d(v, u)}
+
+    where `d(v, u)` is the shortest-path distance between `v` and `u`.
+
+    If `sources` is given as an argument, the returned harmonic centrality
+    values are calculated as the sum of the reciprocals of the shortest
+    path distances from the nodes specified in `sources` to `u` instead
+    of from all nodes to `u`.
+
+    Notice that higher values indicate higher centrality.
+
+    Parameters
+    ----------
+    G : graph
+      A NetworkX graph
+
+    nbunch : container (default: all nodes in G)
+      Container of nodes for which harmonic centrality values are calculated.
+
+    sources : container (default: all nodes in G)
+      Container of nodes `v` over which reciprocal distances are computed.
+      Nodes not in `G` are silently ignored.
+
+    distance : edge attribute key, optional (default=None)
+      Use the specified edge attribute as the edge distance in shortest
+      path calculations.  If `None`, then each edge will have distance equal to 1.
+
+    Returns
+    -------
+    nodes : dictionary
+      Dictionary of nodes with harmonic centrality as the value.
+
+    See Also
+    --------
+    betweenness_centrality, load_centrality, eigenvector_centrality,
+    degree_centrality, closeness_centrality
+
+    Notes
+    -----
+    If the 'distance' keyword is set to an edge attribute key then the
+    shortest-path length will be computed using Dijkstra's algorithm with
+    that edge attribute as the edge weight.
+
+    References
+    ----------
+    .. [1] Boldi, Paolo, and Sebastiano Vigna. "Axioms for centrality."
+           Internet Mathematics 10.3-4 (2014): 222-262.
+    """
+
+    nbunch = set(G.nbunch_iter(nbunch) if nbunch is not None else G.nodes)
+    sources = set(G.nbunch_iter(sources) if sources is not None else G.nodes)
+
+    centrality = {u: 0 for u in nbunch}
+
+    transposed = False
+    if len(nbunch) < len(sources):
+        transposed = True
+        nbunch, sources = sources, nbunch
+        if nx.is_directed(G):
+            G = nx.reverse(G, copy=False)
+
+    spl = partial(nx.shortest_path_length, G, weight=distance)
+    for v in sources:
+        dist = spl(v)
+        for u in nbunch.intersection(dist):
+            d = dist[u]
+            if d == 0:  # handle u == v and edges with 0 weight
+                continue
+            centrality[v if transposed else u] += 1 / d
+
+    return centrality