Python Topology.node[v]['type']方法代码示例

# 需要导入模块: from fnss.topologies.topology import Topology [as 别名]
# 或者: from fnss.topologies.topology.Topology import node[v]['type'] [as 别名]
def star_topology(n):
    """
    Return a star (a.k.a hub-and-spoke) topology of :math:`n+1` nodes

    The root (hub) node has id 0 while all leaf (spoke) nodes have id
    :math:`(1, n+1)`.

    Each node has the attribute type which can either be *root* (for node 0) or
    *leaf* for all other nodes

    Parameters
    ----------
    n : int
        The number of leaf nodes

    Returns
    -------
    topology : A Topology object
    """
    if not isinstance(n, int):
        raise TypeError('n argument must be of int type')
    if n < 1:
        raise ValueError('n argument must be a positive integer')
    G = Topology(nx.star_graph(n))
    G.name = "star_topology(%d)" % (n)
    G.graph['type'] = 'star'
    G.node[0]['type'] = 'root'
    for v in range(1, n + 1):
        G.node[v]['type'] = 'leaf'
    return G

# 需要导入模块: from fnss.topologies.topology import Topology [as 别名]
# 或者: from fnss.topologies.topology.Topology import node[v]['type'] [as 别名]
def k_ary_tree_topology(k, h):
    """
    Return a balanced k-ary tree topology of with depth h
    
    Each node has two attributes:
     * type: which can either be *root*, *intermediate* or *leaf*
     * depth:math:`(0, h)` the height of the node in the tree, where 0 is the
       root and h are leaves.
    
    Parameters
    ----------
    k : int
        The branching factor of the tree
    h : int 
        The height or depth of the tree

    Returns
    -------
    topology : A Topology object
    """
    if not isinstance(k, int) or not isinstance(h, int):
        raise TypeError('k and h arguments must be of int type')
    if k <= 1:
        raise ValueError("Invalid k parameter. It should be > 1")
    if h < 1:
        raise ValueError("Invalid h parameter. It should be >=1")
    G = Topology(nx.balanced_tree(k, h))
    G.name = "k_ary_tree_topology(%d,%d)" % (k, h)
    G.graph['type'] = 'tree'
    G.graph['k'] = k
    G.graph['h'] = h
    G.node[0]['type'] = 'root'
    G.node[0]['depth'] = 0
    # Iterate through the tree to assign labels to nodes
    v = 1
    for depth in range(1, h + 1):
        for _ in range(k**depth):
            G.node[v]['depth'] = depth
            if depth == h:
                G.node[v]['type'] = 'leaf'
            else:
                G.node[v]['type'] = 'intermediate'
            v += 1                   
    return G

# 需要导入模块: from fnss.topologies.topology import Topology [as 别名]
# 或者: from fnss.topologies.topology.Topology import node[v]['type'] [as 别名]
def dumbbell_topology(m1, m2):
    """
    Return a dumbbell topology consisting of two star topologies
    connected by a path.

    More precisely, two star graphs :math:`K_{m1}` form the left and right
    bells, and are connected by a path :math:`P_{m2}`.

    The :math:`2*m1+m2`  nodes are numbered as follows.
     * :math:`0,...,m1-1` for the left barbell,
     * :math:`m1,...,m1+m2-1` for the path,
     * :math:`m1+m2,...,2*m1+m2-1` for the right barbell.

    The 3 subgraphs are joined via the edges :math:`(m1-1,m1)` and
    :math:`(m1+m2-1,m1+m2)`. If m2 = 0, this is merely two star topologies
    joined together.

    Please notice that this dumbbell topology is different from the barbell
    graph generated by networkx's barbell_graph function. That barbell graph
    consists of two complete graphs connected by a path. This consists of two
    stars whose roots are connected by a path. This dumbbell topology is
    particularly useful for simulating transport layer protocols.

    All nodes and edges of this topology have an attribute *type* which can be
    either *right bell*, *core* or *left_bell*

    Parameters
    ----------
    m1 : int
        The number of nodes in each bell
    m2 : int
        The number of nodes in the path

    Returns
    -------
    topology : A Topology object
    """
    if not isinstance(m1, int) or not isinstance(m2, int):
        raise TypeError('m1 and m2 arguments must be of int type')
    if m1 < 2:
        raise ValueError("Invalid graph description, m1 should be >= 2")
    if m2 < 1:
        raise ValueError("Invalid graph description, m2 should be >= 1")

    G = Topology(type='dumbbell')
    G.name = "dumbbell_topology(%d,%d)" % (m1, m2)

    # left bell
    G.add_node(m1)
    for v in range(m1):
        G.add_node(v, type='left_bell')
        G.add_edge(v, m1, type='left_bell')

    # right bell
    for v in range(m1):
        G.add_node(v + m1 + m2, type='right_bell')
        G.add_edge(v + m1 + m2, m1 + m2 - 1, type='right_bell')

    # connecting path
    for v in range(m1, m1 + m2 - 1):
        G.node[v]['type'] = 'core'
        G.add_edge(v, v + 1, type='core')
    G.node[m1 + m2 - 1]['type'] = 'core'

    return G