KNN算法处理mongodb数据

Question

今天看别人的代码，写的是处理mysql的数据，想改成处理mongo数据怎么改啊
我稍微尝试了一下,其实就改了个数据库连接那块

import pandas as pd
from sklearn.cluster import KMeans
from pandas import DataFrame
from scipy.cluster.hierarchy import linkage,dendrogram
import matplotlib.pyplot as plt
import pymongo

if __name__ == '__main__':
    conn = pymongo.MongoClient()

    # cursor = conn.cursor()
    # sql = "select * from DB"
    # cursor.execute(sql)
    results = conn.db.xinxi.find()

    resultList = []

    for result in results:
        resultList.append(result)

    # print(resultList)

    df = DataFrame(resultList)
    # print(df.head())

    # 绘制散点图 评分，参与评论人数
    plt.figure(figsize=(10, 8))
    plt.scatter(df[8].astype(float), df[7].astype(float))
    plt.show()

    scoreDf = pd.DataFrame(df, columns=[7, 8])
    scoreDf.head()

    k = 6  # 聚类的类别
    iteration = 500  # 聚类最大循环次数
    model = KMeans(n_clusters=k,
                   n_jobs=1,
                   max_iter=iteration)  # 分为k类，并发数1，数值大系统卡死
    model.fit(scoreDf)  # 开始聚类

    # 详细输出原始数据及其类别
    res = pd.concat([df,
                     pd.Series(model.labels_, index=df.index)],
                    axis=1)  # 详细输出每个样本对应的类别
    res.columns = list(df.columns) + [u'class']  # 重命名表头

    # 根据聚类画出分类统计图
    for col in res.columns:
        if col in [u'class']:
            fig = plt.figure()
            res[col].hist(bins=20)
            fig.show()

    res.to_excel('knn_result.xls')  # 保存结果

这个是运行成果，请问该怎么写呢，我刚学

D:\Anaconda\Anaconda\python.exe D:/PyCharm/DouBanScrapy-master/code/FisrtKNN.py
Traceback (most recent call last):
  File "D:\Anaconda\Anaconda\lib\site-packages\pandas\core\indexes\base.py", line 3361, in get_loc
    return self._engine.get_loc(casted_key)
  File "pandas\_libs\index.pyx", line 76, in pandas._libs.index.IndexEngine.get_loc
  File "pandas\_libs\index.pyx", line 108, in pandas._libs.index.IndexEngine.get_loc
  File "pandas\_libs\hashtable_class_helper.pxi", line 5198, in pandas._libs.hashtable.PyObjectHashTable.get_item
  File "pandas\_libs\hashtable_class_helper.pxi", line 5206, in pandas._libs.hashtable.PyObjectHashTable.get_item
KeyError: 8

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "D:\PyCharm\DouBanScrapy-master\code\FisrtKNN.py", line 30, in <module>
    plt.scatter(df[8].astype(float), df[7].astype(float))
  File "D:\Anaconda\Anaconda\lib\site-packages\pandas\core\frame.py", line 3458, in __getitem__
    indexer = self.columns.get_loc(key)
  File "D:\Anaconda\Anaconda\lib\site-packages\pandas\core\indexes\base.py", line 3363, in get_loc
    raise KeyError(key) from err
KeyError: 8

Answer 1

你得先有数据才行