single-pass句子分类

一时失言乱红尘 2021-12-23 03:04 318阅读 0赞

# coding=utf-8
    import numpy as np
    from math import sqrt
    import time
    import matplotlib.pylab as pl
    
    
    # 定义一个簇单元
    class ClusterUnit:
        def __init__(self):
            self.node_list = []  # 该簇存在的节点列表
            self.node_num = 0  # 该簇节点数
            self.centroid = None  # 该簇质心
    
        def add_node(self, node, node_vec):
            """ 为本簇添加指定节点，并更新簇心 node_vec:该节点的特征向量 node:节点 return:null """
            self.node_list.append(node)
            try:
                self.centroid = (self.node_num * self.centroid + node_vec) / (self.node_num + 1)  # 更新簇心
            except TypeError:
                self.centroid = np.array(node_vec) * 1  # 初始化质心
            self.node_num += 1  # 节点数加1
    
        def remove_node(self, node):
            # 移除本簇指定节点
            try:
                self.node_list.remove(node)
                self.node_num -= 1
            except ValueError:
                raise ValueError("%s not in this cluster" % node)  # 该簇本身就不存在该节点，移除失败
    
        def move_node(self, node, another_cluster):
            # 将本簇中的其中一个节点移至另一个簇
            self.remove_node(node=node)
            another_cluster.add_node(node=node)
    
    
    # cluster_unit = ClusterUnit()
    # cluster_unit.add_node(1, [1, 1, 2])
    # cluster_unit.add_node(5, [2, 1, 2])
    # cluster_unit.add_node(3, [3, 1, 2])
    # print(cluster_unit.centroid)
    
    
    # 计算向量a与向量b的欧式距离
    def euclidian_distance(vec_a, vec_b):
        diff = vec_a - vec_b
        return sqrt(np.dot(diff, diff))             # dot计算矩阵内积
    
    
    class OnePassCluster:
        def __init__(self, t, vector_list):
            # t:一趟聚类的阈值
            self.threshold = t                      # 一趟聚类的阈值
            self.vectors = np.array(vector_list)    # 数据列表（向量列表）
            self.cluster_list = []                  # 聚类后簇的列表
    
            t1 = time.time()
            self.clustering()
            t2 = time.time()
            self.cluster_num = len(self.cluster_list)       # 聚类完成后 簇的个数
            self.spend_time = t2 - t1                       # 聚类花费的时间
    
        def clustering(self):
            self.cluster_list.append(ClusterUnit())                 # 初始新建一个簇
            self.cluster_list[0].add_node(0, self.vectors[0])       # 将读入的第一个节点归于该簇
            for index in range(len(self.vectors))[1:]:
                min_distance = euclidian_distance(vec_a=self.vectors[index],
                                                  vec_b=self.cluster_list[0].centroid)  # 与簇的质心的最小距离
                min_cluster_index = 0  # 最小距离的簇的索引
                for cluster_index, cluster in enumerate(self.cluster_list[1:]):
                    # enumerate会将数组或列表组成一个索引序列
                    # 寻找距离最小的簇，记录下距离和对应的簇的索引
                    distance = euclidian_distance(vec_a=self.vectors[index],
                                                  vec_b=cluster.centroid)
                    if distance < min_distance:
                        min_distance = distance
                        min_cluster_index = cluster_index + 1
                if min_distance < self.threshold:                   # 最小距离小于阈值，则归于该簇
                    self.cluster_list[min_cluster_index].add_node(index, self.vectors[index])
                else:  # 否则新建一个簇
                    new_cluster = ClusterUnit()
                    new_cluster.add_node(index, self.vectors[index])
                    self.cluster_list.append(new_cluster)
                    del new_cluster
    
        def print_result(self, label_dict=None):
            # 打印出聚类结果
            # label_dict:节点对应的标签字典
            print("*********** single-pass的聚类结果展示 ***********")
            for index, cluster in enumerate(self.cluster_list):
                print("cluster:%s" % index)         # 簇的序号
                print(cluster.node_list)            # 该簇的节点列表
                if label_dict is not None:
                    print(" ".join([label_dict[n] for n in cluster.node_list]))     # 若有提供标签字典，则输出该簇的标签
                print("node num: %s" % cluster.node_num)
                print( "-------------")
            print( "所有节点的个数为： %s" % len(self.vectors))
            print("簇类的个数为：%s" % self.cluster_num)
            print("花费的时间为： %.9fs" % (self.spend_time / 1000))
    
    
    
    # 读取测试集
    temperature_all_city = np.loadtxt('data/c2.txt', delimiter=",", usecols=(3, 4))  # 读取聚类特征
    xy = np.loadtxt('data/c2.txt', delimiter=",", usecols=(8, 9))  # 读取各地经纬度
    f = open('data/c2.txt', 'r')
    lines = f.readlines()
    zone_dict = [i.split(',')[1] for i in lines]  # 读取地区并转化为字典
    
    f.close()
    
    # 构建一趟聚类器
    clustering = OnePassCluster(vector_list=temperature_all_city, t=9)
    clustering.print_result(label_dict=zone_dict)
    print(temperature_all_city)
    
    
    # 将聚类结果导出图
    fig, ax = pl.subplots()
    fig = zone_dict
    c_map = pl.get_cmap('jet', clustering.cluster_num)
    c = 0
    
    for cluster in clustering.cluster_list:
        for node in cluster.node_list:
            #ax.scatter(xy[node][0], xy[node][1], c=c, s=30, cmap=c_map, vmin=0, vmax=clustering.cluster_num)
            ax.scatter(xy[node][0], xy[node][1])
        c += 1
    
    pl.show()