Timedelta là sự khác biệt về thời gian, được thể hiện bằng các đơn vị khác nhau, ví dụ như ngày, giờ, phút, giây. Chúng có thể là số dương hoặc số âm. Chúng ta có thể tạo các đối tượng Timedelta bằng nhiều đối số khác nhau như được hiển thị bên dưới−
String
By passing a string literal, we can create a timedelta object.
import pandas as pd print pd.Timedelta(''2 days 2 hours 15 minutes 30 seconds'')
Its output is as follows −
2 days 02:15:30
Integer
By passing an integer value with the unit, an argument creates a Timedelta object.
import pandas as pd print pd.Timedelta(6,unit=''h'')
Its output is as follows −
0 days 06:00:00
Data Offsets
Data offsets such as – weeks, days, hours, minutes, seconds, milliseconds, microseconds, nanoseconds can also be used in construction.
import pandas as pd print pd.Timedelta(days=2)
Its output is as follows −
2 days 00:00:00
to_timedelta()
Using the top-level pd.to_timedelta, you can convert a scalar, array, list, or series from a recognized timedelta format/ value into a Timedelta type. It will construct Series if the input is a Series, a scalar if the input is scalar-like, otherwise will output a TimedeltaIndex.
import pandas as pd print pd.Timedelta(days=2)
Its output is as follows −
2 days 00:00:00
Operations
You can operate on Series/ DataFrames and construct timedelta64[ns] Series through subtraction operations on datetime64[ns] Series, or Timestamps.
Let us now create a DataFrame with Timedelta and datetime objects and perform some arithmetic operations on it −
import pandas as pd s = pd.Series(pd.date_range(''2012-1-1'', periods=3, freq=''D'')) td = pd.Series([ pd.Timedelta(days=i) for i in range(3) ]) df = pd.DataFrame(dict(A = s, B = td)) print df
Its output is as follows −
A B 0 2012-01-01 0 days 1 2012-01-02 1 days 2 2012-01-03 2 days
Addition Operations
import pandas as pd s = pd.Series(pd.date_range(''2012-1-1'', periods=3, freq=''D'')) td = pd.Series([ pd.Timedelta(days=i) for i in range(3) ]) df = pd.DataFrame(dict(A = s, B = td)) df[''C'']=df[''A'']+df[''B''] print df
Its output is as follows −
A B C 0 2012-01-01 0 days 2012-01-01 1 2012-01-02 1 days 2012-01-03 2 2012-01-03 2 days 2012-01-05
Subtraction Operation
import pandas as pd s = pd.Series(pd.date_range(''2012-1-1'', periods=3, freq=''D'')) td = pd.Series([ pd.Timedelta(days=i) for i in range(3) ]) df = pd.DataFrame(dict(A = s, B = td)) df[''C'']=df[''A'']+df[''B''] df[''D'']=df[''C'']+df[''B''] print df
Its output is as follows −
A B C D 0 2012-01-01 0 days 2012-01-01 2012-01-01 1 2012-01-02 1 days 2012-01-03 2012-01-04 2 2012-01-03 2 days 2012-01-05 2012-01-07
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