Python Pandas - Return the frequency object as a string from the PeriodIndex object

To return the frequency object as a string from the PeriodIndex object, use the PeriodIndex.freqstr property. This property provides a string representation of the frequency, which is useful for display and debugging purposes.

Creating a PeriodIndex Object

First, let's create a PeriodIndex object with datetime values and a specific frequency ?

import pandas as pd

# Create a PeriodIndex object with minute frequency
periodIndex = pd.PeriodIndex(['2021-09-25 07:50:35', '2019-10-30 04:35:45',
                             '2021-07-15 02:25:15', '2022-06-25 07:20:55'], freq="T")

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

PeriodIndex object:
PeriodIndex(['2021-09-25 07:50', '2019-10-30 04:35', '2021-07-15 02:25', '2022-06-25 07:20'],
dtype='period[T]')

Using freqstr Property

The freqstr property returns the frequency as a string representation ?

import pandas as pd

periodIndex = pd.PeriodIndex(['2021-09-25 07:50:35', '2019-10-30 04:35:45',
                             '2021-07-15 02:25:15', '2022-06-25 07:20:55'], freq="T")

# Compare frequency object vs frequency string
print("Frequency object:")
print(periodIndex.freq)
print("\nFrequency as string:")
print(periodIndex.freqstr)
print(f"\nType of freqstr: {type(periodIndex.freqstr)}")

Frequency object:
<Minute>

Frequency as string:
T

Type of freqstr: <class 'str'>

Different Frequency Examples

Here are examples with different frequency types ?

import pandas as pd

# Daily frequency
daily_idx = pd.PeriodIndex(['2021-01-01', '2021-01-02', '2021-01-03'], freq='D')
print(f"Daily frequency string: {daily_idx.freqstr}")

# Monthly frequency
monthly_idx = pd.PeriodIndex(['2021-01', '2021-02', '2021-03'], freq='M')
print(f"Monthly frequency string: {monthly_idx.freqstr}")

# Hourly frequency
hourly_idx = pd.PeriodIndex(['2021-01-01 10:00', '2021-01-01 11:00'], freq='H')
print(f"Hourly frequency string: {hourly_idx.freqstr}")

Daily frequency string: D
Monthly frequency string: M
Hourly frequency string: H

Conclusion

The freqstr property provides a convenient way to get the string representation of a PeriodIndex frequency. This is particularly useful when you need to display or store frequency information in a human-readable format.