Pandas – 两个日期之间的月数

在本文中，我们将使用Python查找 pandas 中两个日期之间的月数。

示例 1：

我们将获取一个数据框，并为我们想要获得差异的日期提供两列。使用 df.dates1-df.dates2 求两个日期的差，然后将结果转换为月份的形式。转换为“int”数据类型，否则结果将采用浮点形式。

Python3

# Importing required libraries
import pandas as pd
import numpy as np
import datetime
 
# Making a dataframe which will have two
# columns two store different dates
df = pd.DataFrame({'dates1': np.array(
  [datetime.datetime(2000, 10, 19), datetime.datetime(2021, 1, 8)]),
                   'dates2': np.array(
                     [datetime.datetime(1998, 6, 20),
                      datetime.datetime(2012, 10, 18)])})
 
# Used to convert the difference in terms of months
df['nb_months'] = ((df.dates1 - df.dates2)/np.timedelta64(1, 'M'))
df['nb_months'] = df['nb_months'].astype(int)
print(df)

输出：

示例 2：

我们还可以通过对代码稍作修改来获取两个日期之间的天数。如下图所示：

Python3

# Importing required libraries
import pandas as pd
import numpy as np
import datetime
 
# Making a dataframe which will have
# two columns two store different dates
df = pd.DataFrame({'dates1': np.array(
  [datetime.datetime(2000, 10, 19), datetime.datetime(2021, 1, 8)]),
                   'dates2': np.array(
                     [datetime.datetime(1998, 6, 20),
                      datetime.datetime(2012, 10, 18)])})
 
# Used to convert the difference in terms of days
df['Number_of_days'] = ((df.dates1 - df.dates2)/np.timedelta64(1, 'D'))
df['Number_of_days'] = df['Number_of_days'].astype(int)
print(df)

输出：

示例 3：

以类似的方式，我们也可以在周数方面得到两个日期之间的差异。

Python3

# Importing required libraries
import pandas as pd
import numpy as np
import datetime
 
# Making a dataframe which will
# have two columns two store different dates
df= pd.DataFrame({'dates1': np.array(
  [datetime.datetime(2000, 10, 19), datetime.datetime(2021, 1, 8)]),
                   'dates2': np.array(
                     [datetime.datetime(1998, 6, 20),
                      datetime.datetime(2012, 10, 18)] )})
 
# Used to convert the difference in terms of weeks
df['Number_of_weeks'] = ((df.dates1 - df.dates2)/np.timedelta64(1, 'W'))
df['Number_of_weeks'] = df['Number_of_weeks'].astype(int)
print(df)

输出：

示例 4：

以类似的方式，我们也可以在年份方面获得两个日期之间的差异。

Python3

# Importing required libraries
import pandas as pd
import numpy as np
import datetime
 
# Making a dataframe which will
# have two columns two store different dates
df = pd.DataFrame({'dates1': np.array(
  [datetime.datetime(2000, 10, 19), datetime.datetime(2021, 1, 8)]),
                   'dates2': np.array(
                     [datetime.datetime(1998, 6, 20),
                      datetime.datetime(2012, 10, 18)])})
 
# Used to convert the difference in terms of years
df['Number_of_years'] = ((df.dates1 - df.dates2)/np.timedelta64(1, 'Y'))
df['Number_of_years'] = df['Number_of_years'].astype(int)
print(df)

输出：