Python Pandas - Perform ceil operation on the TimeDeltaIndex object with milliseconds frequency

To perform ceil operation on the TimeDeltaIndex with milliseconds frequency, use the TimeDeltaIndex.ceil() method. For milliseconds frequency, use the freq parameter with value 'ms'.

What is the Ceil Operation?

The ceil operation rounds up time values to the next specified frequency boundary. When applied with milliseconds frequency, it rounds up to the nearest millisecond ?

Creating a TimeDeltaIndex Object

First, create a TimeDeltaIndex object with various time delta values ?

import pandas as pd

# Create a TimeDeltaIndex object with timedelta-like data
tdIndex = pd.TimedeltaIndex(data=['4 day 8h 20min 35us 45ns', '+17:42:19.999999',
                                  '9 day 3h 08:16:02.000055', '+22:35:25.000075'])

print("TimedeltaIndex...")
print(tdIndex)

TimedeltaIndex...
TimedeltaIndex(['4 days 08:20:00.000035045', '0 days 17:42:19.999999',
                '9 days 11:16:02.000055', '0 days 22:35:25.000075'],
               dtype='timedelta64[ns]', freq=None)

Viewing Components

You can view the individual components of the TimeDelta values ?

import pandas as pd

tdIndex = pd.TimedeltaIndex(data=['4 day 8h 20min 35us 45ns', '+17:42:19.999999',
                                  '9 day 3h 08:16:02.000055', '+22:35:25.000075'])

print("Components of TimeDeltas:")
print(tdIndex.components)

Components of TimeDeltas:
   days  hours  minutes  seconds  milliseconds  microseconds  nanoseconds
0     4      8       20        0             0            35           45
1     0     17       42       19           999           999            0
2     9     11       16        2             0            55            0
3     0     22       35       25             0            75            0

Performing Ceil Operation with Milliseconds Frequency

Use the ceil() method with freq='ms' to round up to the nearest millisecond ?

import pandas as pd

tdIndex = pd.TimedeltaIndex(data=['4 day 8h 20min 35us 45ns', '+17:42:19.999999',
                                  '9 day 3h 08:16:02.000055', '+22:35:25.000075'])

print("Original TimedeltaIndex:")
print(tdIndex)

print("\nAfter Ceil operation with milliseconds frequency:")
result = tdIndex.ceil(freq='ms')
print(result)

Original TimedeltaIndex:
TimedeltaIndex(['4 days 08:20:00.000035045', '0 days 17:42:19.999999',
                '9 days 11:16:02.000055', '0 days 22:35:25.000075'],
               dtype='timedelta64[ns]', freq=None)

After Ceil operation with milliseconds frequency:
TimedeltaIndex(['4 days 08:20:00.001000', '0 days 17:42:20',
                '9 days 11:16:02.001000', '0 days 22:35:25.001000'],
               dtype='timedelta64[ns]', freq=None)

How It Works

The ceil operation rounds up each TimeDelta value:

• '4 days 08:20:00.000035045' ? '4 days 08:20:00.001000' (rounds up microseconds/nanoseconds to next millisecond)
• '0 days 17:42:19.999999' ? '0 days 17:42:20' (rounds up to next second since already at 999.999ms)
• '9 days 11:16:02.000055' ? '9 days 11:16:02.001000' (rounds up microseconds to next millisecond)
• '0 days 22:35:25.000075' ? '0 days 22:35:25.001000' (rounds up microseconds to next millisecond)

Conclusion

Use TimeDeltaIndex.ceil(freq='ms') to round up time delta values to the nearest millisecond boundary. This is useful for standardizing time precision in data analysis.