#only works for undirected graphs
def degreeCentralization():
    maxVar = 0.0
    maxVar = (len(g.nodes)-1) * (len(g.nodes)-2)
    g.nodes[0].totaldegree
    var = 0.0
    max = totaldegree.max
    for x in range(totaldegree.max+1):
        list = (totaldegree == x)
        for node in list:
            var += (max - node.totaldegree)          

    
    return var/maxVar

# I am not sure what this works on. I would only completely trust 
# the results on undirected graphs. Graphs do NOT have to be connected
def betweenCentralization():
    numNodes = len(g.nodes)
    maxVar = ((numNodes -1.0) * (numNodes-2.0))*(numNodes-1)
    g.nodes[0].betweenness
    max = betweenness.max
    var = 0.0
    for node in g.nodes:
        var += (max - node.betweenness)
    
    return var/maxVar

# only works for undirected, connected graphs
def closeCentrality(node):
    total = 0.0
    numVertices = len(g.nodes) - 1
    for nodeTwo in g.nodes:
        list = node.unweightedShortestPath(nodeTwo)
        total += len(list)
   
    return numVertices/total
# only for undirected, connected graphs
def closeCentralization():
    numNodes = len(g.nodes)
    point = (1.0 - (numNodes-1.0)/(((numNodes-2.0) *2.0)+1.0))
    maxVar =  (numNodes-1)*point
    var = 0.0
    if(Node.getField("closeness") == None):
        addNodeField("closeness", Types.DOUBLE, 0.0)
    for node in g.nodes:
        centrality = closeCentrality(node)
        node.closeness = centrality
    max = closeness.max
    for node in g.nodes:
        var += (max - node.closeness)
   
    return var/maxVar