zoukankan      html  css  js  c++  java
  • DataFrame-选择与切片

    取得DataFrame对象reviews的description列的前10个值(或者说reviews前10行的description列):

    reviews.iloc[:10].loc[:,'description'] 等价于 reviews[:10]['description']

    kaggles练习(https://www.kaggle.com/morein2008/indexing-selecting-assigning/edit)答案:

    reviews.loc[reviews['country'].isin(['Italy','France']) & (reviews['points']>=90),['country','points']]
    reviews.loc[reviews['country']=='Italy']['points']
    reviews.iloc[:-1000:-1]['points']
    reviews.iloc[:1000]['points']
    reviews['points']
    check_q9(reviews.loc[reviews['region_2'].isnull()==False,])
    check_q8(reviews.loc[reviews['country']=='Italy',])
    check_q7(reviews.iloc[:100,][['country','variety']])
    check_q6(reviews.iloc[[0,1,10,100],][['country','province','region_1','region_2']])
    check_q5(reviews.iloc[[1,2,3,5,8],])
    check_q4(reviews.iloc[:10,].loc[:,'description'])
    check_q3(reviews.iloc[0])
    check_q2(reviews['description'][0])
    check_q1(reviews['description'])

  • 相关阅读:
    5.5 数据库约束
    5.4 数据库数据类型
    5.3 数据 库,表 操作
    5.2 数据库引擎
    5.1 数据库安装
    4.6 并发编程/IO模型
    4.5 协程
    4.4 线程
    在线编辑器 引入方法
    MySQL查看版本号的五种方式介绍1111111
  • 原文地址:https://www.cnblogs.com/aaronhoo/p/9508902.html
Copyright © 2011-2022 走看看