This is a bug, referenced in GH9413 and GH16211.
The reason, as given by the devs -
It looks like the difference here is that
quantileandpercentiletake the weighted average of the nearest points, whereas rolling_quantile simply uses one the nearest point (no averaging).
Rolling.quantile did not interpolate when computing the quantiles.
The bug has been fixed as of 0.21.
For older versions, the fix is using a rolling_apply.
df.rolling(window=3, center=False).apply(lambda x: pd.Series(x).quantile(0.75))
0
0 NaN
1 NaN
2 2.5
3 2.5
4 2.5
5 2.5
6 2.5
7 2.5
8 2.5
Answer from coldspeed95 on Stack OverflowStatology
statology.org › home › how to use rolling.quantile() function in pandas
How to Use Rolling.quantile() Function in Pandas
April 23, 2024 - The easiest way to calculate a rolling quantile in pandas is by using the rolling.quantile() function, which uses the following basic syntax:
Pandas
pandas.pydata.org › pandas-docs › stable › reference › api › pandas.core.window.rolling.Rolling.quantile.html
pandas.core.window.rolling.Rolling.quantile — pandas 2.3.3 documentation
This optional parameter specifies ... desired quantile lies between two data points i and j: linear: i + (j - i) * fraction, where fraction is the fractional part of the index surrounded by i and j. ... Include only float, int, boolean columns. Added in version 1.5.0. ... Return type is the same as the original object with np.float64 dtype. ... Calling rolling with Series ...
Intelpython
intelpython.github.io › sdc-doc › latest › _api_ref › pandas.core.window.Rolling.quantile.html
pandas.core.window.Rolling.quantile — Intel® Scalable Dataframe Compiler 0.1 documentation
import pandas as pd from numba import njit @njit def series_rolling_quantile(): series = pd.Series([4, 3, 5, 2, 6]) # Series of 4, 3, 5, 2, 6 out_series = series.rolling(3).quantile(0.25) return out_series # Expect series of NaN, NaN, 3.5, 2.5, 3.5 print(series_rolling_quantile())
Pandas
pandas.pydata.org › pandas-docs › version › 2.0 › reference › api › pandas.core.window.rolling.Rolling.quantile.html
pandas.core.window.rolling.Rolling.quantile — pandas 2.0.3 documentation
This optional parameter specifies ... desired quantile lies between two data points i and j: linear: i + (j - i) * fraction, where fraction is the fractional part of the index surrounded by i and j. ... Include only float, int, boolean columns. New in version 1.5.0. ... Return type is the same as the original object with np.float64 dtype. ... Calling rolling with Series ...
Pandas
pandas.pydata.org › pandas-docs › version › 0.25.3 › reference › api › pandas.core.window.Rolling.quantile.html
pandas.core.window.Rolling.quantile — pandas 0.25.3 documentation
Computes values at the given quantile over requested axis in DataFrame. ... >>> s = pd.Series([1, 2, 3, 4]) >>> s.rolling(2).quantile(.4, interpolation='lower') 0 NaN 1 1.0 2 2.0 3 3.0 dtype: float64
Pandas
pandas.pydata.org › docs › dev › reference › api › pandas.core.window.rolling.Rolling.quantile.html
pandas.core.window.rolling.Rolling.quantile — pandas 3.0.0.dev0+2382.g29ce48952a documentation
This optional parameter specifies ... desired quantile lies between two data points i and j: linear: i + (j - i) * fraction, where fraction is the fractional part of the index surrounded by i and j. ... Include only float, int, boolean columns. Added in version 1.5.0. ... Return type is the same as the original object with np.float64 dtype. ... Calling rolling with Series ...
Pandas
pandas.pydata.org › pandas-docs › version › 0.18 › generated › pandas.core.window.Rolling.quantile.html
pandas.core.window.Rolling.quantile — pandas 0.18.1 documentation
pandas.core.window.Rolling.quantile · pandas.core.window.Window.mean · pandas.core.window.Window.sum · Standard expanding window functions · Exponentially-weighted moving window functions · GroupBy · Resampling · Style · General utility functions · Internals · Release Notes ·
Pandas
pandas.pydata.org › pandas-docs › version › 2.1.4 › reference › api › pandas.core.window.rolling.Rolling.quantile.html
pandas.core.window.rolling.Rolling.quantile — pandas 2.1.4 documentation
This optional parameter specifies ... desired quantile lies between two data points i and j: linear: i + (j - i) * fraction, where fraction is the fractional part of the index surrounded by i and j. ... Include only float, int, boolean columns. New in version 1.5.0. ... Return type is the same as the original object with np.float64 dtype. ... Calling rolling with Series ...
Pandas
pandas.pydata.org › pandas-docs › version › 0.20 › generated › pandas.core.window.Rolling.quantile.html
pandas.core.window.Rolling.quantile — pandas 0.20.3 documentation
pandas.core.window.Rolling.quantile · pandas.core.window.Window.mean · pandas.core.window.Window.sum · Standard expanding window functions · Exponentially-weighted moving window functions · GroupBy · Resampling · Style · General utility functions · Internals · Release Notes ·
Pandas
pandas.pydata.org › pandas-docs › stable › reference › api › pandas.DataFrame.quantile.html
pandas.DataFrame.quantile — pandas 3.0.5 documentation
Whether to compute quantiles per-column (‘single’) or over all columns (‘table’). When ‘table’, the only allowed interpolation methods are ‘nearest’, ‘lower’, and ‘higher’. ... Rolling quantile.
Apache
spark.apache.org › docs › latest › api › python › reference › pyspark.pandas › api › pyspark.pandas.window.Rolling.quantile.html
pyspark.pandas.window.Rolling.quantile — PySpark 4.1.1 documentation
For DataFrame, each rolling quantile is computed column-wise. >>> df = ps.DataFrame({"A": s.to_numpy(), "B": s.to_numpy() ** 2}) >>> df A B 0 4 16 1 3 9 2 5 25 3 2 4 4 6 36 · >>> df.rolling(2).quantile(0.5) A B 0 NaN NaN 1 3.0 9.0 2 3.0 9.0 3 2.0 4.0 4 2.0 4.0
Pandas
pandas.pydata.org › pandas-docs › stable › reference › api › pandas.api.typing.Rolling.quantile.html
pandas.api.typing.Rolling.quantile — pandas 3.0.0 documentation
This optional parameter specifies ... desired quantile lies between two data points i and j: linear: i + (j - i) * fraction, where fraction is the fractional part of the index surrounded by i and j. ... Include only float, int, boolean columns. ... Return type is the same as the original object with np.float64 dtype. ... Calling rolling with Series ...
Pandas
pandas.pydata.org › pandas-docs › version › 0.23.1 › generated › pandas.core.window.Rolling.quantile.html
pandas.core.window.Rolling.quantile — pandas 0.23.1 documentation
Computes values at the given quantile over requested axis in DataFrame. ... >>> s = pd.Series([1, 2, 3, 4]) >>> s.rolling(2).quantile(.4, interpolation='lower') 0 NaN 1 1.0 2 2.0 3 3.0 dtype: float64
Arabpsychology
statistics.arabpsychology.com › home › a comprehensive guide to calculating rolling quantiles in pandas
A Comprehensive Guide To Calculating Rolling Quantiles In Pandas - PSYCHOLOGICAL STATISTICS
November 13, 2025 - The most straightforward and efficient mechanism for computing a rolling quantile within the Pandas ecosystem involves chaining the rolling.quantile() function. This method must follow the initial .rolling(window_size) operation, which explicitly dictates the width of the temporal window used for the calculation.
Starred by 138 users
Forked by 4 users
Languages: C 86.6% | Python 13.4%
Apache
dlcdn.apache.org › spark › docs › 3.4.2 › api › python › reference › pyspark.pandas › api › pyspark.pandas.window.Rolling.quantile.html
pyspark.pandas.window.Rolling.quantile — PySpark 3.4.2 documentation
Rolling.quantile(quantile: float, accuracy: int = 10000) → FrameLike[source]¶
Runebook.dev
runebook.dev › en › docs › pandas › reference › api › pandas.core.window.rolling.rolling.quantile
Troubleshooting pandas.DataFrame.rolling().quantile() in Python
rolling_quantiles = numeric_df.rolling(window=3).quantile(0.5) print("\nSolution:") print(rolling_quantiles) The window parameter can be a bit confusing. It's not just about the number of rows; it can also be a time offset if your index is a DatetimeIndex. If you have a time-series dataset but use an integer for the window, you might not get the result you expect, especially if there are missing dates. import pandas as pd import numpy as np # A time series with a gap dates = pd.to_datetime(['2025-01-01', '2025-01-02', '2025-01-05', '2025-01-06']) data = {'A': [10, 20, 30, 40]} ts = pd.Series(data['A'], index=dates) # This uses a fixed number of rows, ignoring the date gap print("Result using fixed window size:") print(ts.rolling(window=3).quantile(0.5))
Pandas
pandas.pydata.org › docs › reference › api › pandas.DataFrame.quantile.html
pandas.DataFrame.quantile — pandas 3.0.6 documentation
Whether to compute quantiles per-column (‘single’) or over all columns (‘table’). When ‘table’, the only allowed interpolation methods are ‘nearest’, ‘lower’, and ‘higher’. ... Rolling quantile.