pandas.infer_freq

pandas.infer_freq(index)

Infer the most likely frequency given the input index.

This method attempts to deduce the most probable frequency (e.g., ‘D’ for daily, ‘H’ for hourly) from a sequence of datetime-like objects. It is particularly useful when the frequency of a time series is not explicitly set or known but can be inferred from its values.

Parameters:

indexDatetimeIndex, TimedeltaIndex, Series or array-like

If passed a Series will use the values of the series (NOT THE INDEX).

Returns:

str or None

None if no discernible frequency.

Raises:

TypeError

If the index is not datetime-like.

ValueError

If there are fewer than three values.

See also

date_range

Return a fixed frequency DatetimeIndex.

timedelta_range

Return a fixed frequency TimedeltaIndex with day as the default.

period_range

Return a fixed frequency PeriodIndex.

DatetimeIndex.freq

Return the frequency object if it is set, otherwise None.

Examples

>>> idx = pd.date_range(start="2020/12/01", end="2020/12/30", periods=30)
>>> pd.infer_freq(idx)
'D'