Python Pandas - Get the month number of the period from the PeriodIndex object

To get the month number from a PeriodIndex object in Pandas, use the month property. This returns month numbers where January=1, February=2, ..., December=12.

Syntax

PeriodIndex.month

Creating a PeriodIndex Object

First, let's create a PeriodIndex object with different dates ?

import pandas as pd

# Create a PeriodIndex object with minute frequency
periodIndex = pd.PeriodIndex(['2021-09-25 07:30:35', '2019-10-30 04:15:45',
                              '2021-07-15 02:55:15', '2022-06-25 09:40:55'], freq="T")

print("PeriodIndex object:")
print(periodIndex)

PeriodIndex object:
PeriodIndex(['2021-09-25 07:30', '2019-10-30 04:15', '2021-07-15 02:55', '2022-06-25 09:40'], dtype='period[T]')

Getting Month Numbers

Use the month property to extract month numbers from the PeriodIndex ?

import pandas as pd

periodIndex = pd.PeriodIndex(['2021-09-25 07:30:35', '2019-10-30 04:15:45',
                              '2021-07-15 02:55:15', '2022-06-25 09:40:55'], freq="T")

# Get month numbers
months = periodIndex.month
print("Month numbers:")
print(months)
print(f"\nData type: {type(months)}")

Month numbers:
Index([9, 10, 7, 6], dtype='int64')

Data type: <class 'pandas.core.indexes.base.Index'>

Complete Example

Here's a comprehensive example showing PeriodIndex properties and month extraction ?

import pandas as pd

# Create a PeriodIndex object
periodIndex = pd.PeriodIndex(['2021-09-25 07:30:35', '2019-10-30 04:15:45',
                              '2021-07-15 02:55:15', '2022-06-25 09:40:55'], freq="T")

# Display PeriodIndex object
print("PeriodIndex...")
print(periodIndex)

# Display PeriodIndex frequency
print("\nPeriodIndex frequency object...")
print(periodIndex.freq)

# Display PeriodIndex frequency as string
print("\nPeriodIndex frequency object as a string...")
print(periodIndex.freqstr)

# Display month number from the PeriodIndex object
print("\nThe month number from the PeriodIndex object...")
print(periodIndex.month)

PeriodIndex...
PeriodIndex(['2021-09-25 07:30', '2019-10-30 04:15', '2021-07-15 02:55', '2022-06-25 09:40'], dtype='period[T]')

PeriodIndex frequency object...
<Minute>

PeriodIndex frequency object as a string...
T

The month number from the PeriodIndex object...
Index([9, 10, 7, 6], dtype='int64')

Key Points

• The month property returns an Index object containing integer month numbers
• Month numbering follows the standard: January=1, February=2, ..., December=12
• The frequency parameter ("T" for minute) doesn't affect month extraction
• You can access individual month numbers using standard indexing: periodIndex.month[0]

Conclusion

The PeriodIndex.month property provides an efficient way to extract month numbers from period data. It returns an Index object containing integers from 1-12 representing the months in your time series data.