Create 25-TimeDelta.md

Author: DragonflyStats

25-TimeDelta.md

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+Python Pandas - Timedelta
+
+
+Timedeltas are differences in times, expressed in difference units, for example, days, hours, minutes, seconds. They can be both positive and negative.
+We can create Timedelta objects using various arguments as shown below −
+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
+
+