【Python基础】关于日期特征，你想知道操作都在这儿～

# 导入相关库包
import pandas as pd
import numpy as np
import datetime
import time
import random
from calendar import monthrange 

# 捏造数据
df = pd.DataFrame(
      [[1, 1508212054157,'1993-11-03'],
       [2, 1507029571478,'1993-11-04'],
       [3, 1508211513583,'1993-10-03'],
       [4, 1507029532200,'1993-02-03'],
       [5, 1507029671831,'1993-06-20']
      ]
      ,columns=['user_id','timestamp13','date'])

# 捏造 10位的 时间戳
df['timestamp10'] = df['user_id'].apply(lambda x:int(time.time()-10000*x))

df.head()

# 字符串转日期
df['datetime64'] = pd.to_datetime(df['date'])

# 日期转字符串
df['date_str'] = df['datetime64'].apply(lambda x: x.strftime('%Y-%m-%d %H:%M:%S'))

# 13位的时间戳转 日期格式str
df['timestamp13_to_datetime'] = df['timestamp13'].apply(lambda x: \
                                                        time.strftime('%Y-%m-%d %H:%M:%S',time.localtime(x/1000)))

# 13位的时间戳转datetime
df['timestamp13_to_datetime2'] = pd.to_datetime(df['timestamp13_to_datetime'])

# 10位的时间戳转 日期格式str
df['timestamp10_to_datetime'] = df['timestamp10'].apply(lambda x: \
                                                        time.strftime('%Y-%m-%d %H:%M:%S',time.localtime(x)))

# 10位的时间戳转datetime
df['timestamp10_to_datetime2'] = pd.to_datetime(df['timestamp10_to_datetime'])

# 提取月的总天数
def extract_month_range(year, month):
    '''提取这个月的总天数'''
    first_day_of_month, days_in_a_month = monthrange(int(year), int(month))
    return days_in_a_month
df['days_in_a_month'] = df.apply(lambda x: extract_month_range(x['year'], x['month']), axis=1)

# 获取前一天日期
df['yesterday'] = df['datetime64'] - datetime.timedelta(days=1)

# 获取今天日期
df['today'] = datetime.date.today()

# 提取日期实体
df['day'] = df['datetime64'].dt.day #天
df['weekday'] = df['datetime64'].dt.weekday #周
df['month'] = df['datetime64'].dt.month #月
df['year'] = df['datetime64'].dt.year #年

# 日期差计算(天)
df['day_dif'] = (df['datetime64'] - df['yesterday']).dt.days

# 日期差计算(小时)
df['hour_dif'] = (df['datetime64'] - df['yesterday']).values/np.timedelta64(1, 'h') # 换成 D 则为 天