July 2019
Intermediate to advanced
365 pages
8h 13m
Chinese
Content preview from Python机器学习手册：从数据预处理到深度学习
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118
｜
第
7
章
处理日期和时间
#
创建年、月、日、时和分的特征
dataframe['year'] = dataframe['date'].dt.year
dataframe['month'] = dataframe['date'].dt.month
dataframe['day'] = dataframe['date'].dt.day
dataframe['hour'] = dataframe['date'].dt.hour
dataframe['minute'] = dataframe['date'].dt.minute
#
查看
3
行
dataframe.head(3)
date year month day hour minute
0 2001-01-07 2001 1 7 0 0
1
2
2001-01-14
2001-01-21
2001
2001
1
1
14
21
0
0
0
0
讨论
有时候将
date
这一列划分成多个部分是很有用的。比如，你可能需要用一个特征来表示
观察值的年份 ；或者你仅希望考虑观察值的月份以便对它们进行比较，而不管其年份是
多少。
7.5
计算两个日期之间的时间差
问题描述
为每个观察值计算两个日期特征之间的时间差。
解决方案
使用
pandas
对两个日期特征做减法 ：
#
加载库
import pandas as pd
#
创建数据帧
dataframe = pd.DataFrame()
#
创建两个
datetime
特征
dataframe['Arrived'] = [pd.Timestamp('01-01-2017'),pd.Timestamp('01-04-2017')] ...
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