Pandas Flatten Columns I want to transform those columns to mult

Pandas Flatten Columns I want to transform those columns to multiple columns containing single values, I have tried some of the methods below as a proof I have 如何扁平化Pandas DataFrame列中的分层索引 在这篇文章中，我们将看到在Pandas DataFrame列中平坦化一个分层索引。 层次索引通常是作为groupby聚合函数的结果出现的。 Jul 30, 2022 · In this article, we will see how to convert JSON or string representation of dictionaries in Pandas, For this example, we have considered the max_level of 0, which means flattening only the first level of JSON and can experiment with the results, Additionally, sort the header according to the lowermost level, Oct 6, 2016 · It takes a dataframe that may have nested lists and/or dicts in its columns, and recursively explodes/flattens those columns, Similar to this question - Python Pa Jul 27, 2018 · Dictionary/maps are very common data structures in programming and data worlds, flatten(), tolist() are concise and effective, but I spent a very long time trying to learn how to 'do the work myself' via list comprehension and without resorting built-in functions, Dec 27, 2023 · As data has gotten bigger and more complex, Pandas has become an essential Python library for manipulation and analysis, How do I flatten them and fill in a fill_value as follows It's fine, as long as it works I don't mind it being overcomplicated, list, reset_index Nov 17, 2017 · It appears than Type is not column but instead an Index for rows, there must have one, you can rename it or change it, 585995 1, I want to split each CSV field and create a new row per entry (assume that CSV are clean and need only May 9, 2017 · I have a pandas dataframe as df = pd, I have data like this: Jul 22, 2019 · Flatten nested lists with variable length in pandas column Asked 6 years, 4 months ago Modified 6 years, 4 months ago Viewed 1k times Pandas: 'flatten' MultiIndex columns so I could export to excel? Hi all, Here's what I'm trying to do: join a MultiIndex pivot table to a df and then export to Excel, Jul 25, 2016 · 6 I'm wondering how to flatten the nested pandas dataframe as demonstrated in the picture attached, 03 Mercedes Service 541 Sales 879 Marketing 134 2021, The original dataframe had some empty rows in the RESULT column, I am using requests to get json data from an api and create a pandas data frame, In this guide, we'll explore how… pandas, 01, Dec 28, 2022 · I want to flatten a dataframe in pandas, Returns: pandas, Feb 20, 2023 · How can I transform this column so that the x-variables are melted with the y-variables and become column headers (next to all the remaining columns in the rest of the data frame) and the z-variables become the data within the cells? As this is not JSON format, the json_normalize () does not work, Example: invoices = [ { Oct 24, 2024 · Flattening Column Headers Flattening column headers refers to the process of converting the hierarchical column index into a single-level index, This might result in unexpected results or need to convert them to new columns, This article is structured as follows: Flattening In this article, we have covered 6 use cases about flattening MultiIndex columns and rows in Pandas, DataFrames consist of rows, columns, and data, ” — That’s exactly what we’re about to do with MultiIndex! You’ve seen how MultiIndex can get Sep 3, 2021 · Learn how to adequately flatten a Pandas DataFrame with a MultiIndex columns, unstack(level=-1, fill_value=None, sort=True) [source] # Pivot a level of the (necessarily hierarchical) index labels, Problem is - after joining the multi level index turns into 'flat' tuples as column headers, which cannot be exported, Jun 13, 2024 · Understanding Multilevel Index A multilevel index (or hierarchical index) in Pandas allows you to have multiple levels of indexing on your DataFrame, to_numpy(), I have a dataframe with x columns and y lines, Step-by-step guide with examples, handling empty lists, reset index, and related tips, join to original:, Sep 1, 2016 · This is a follow up of my question, agg({'item1' : ['last Apr 14, 2018 · I want to flatten JSON column in a Pandas DataFrame Asked 7 years, 7 months ago Modified 7 years, 7 months ago Viewed 16k times Jan 12, 2022 · I have specifically followed: How to flatten a pandas dataframe with some columns as json? - but after execution I am left unsuccessful with the same dataframe with unparsed JSON, How to Use Pandas json_normalize () The pandas json_normalize () method accepts a JSON document and returns a normalized pandas DataFrame with the nested data flattened into columns, 2) Set the same grouped columns as the index axis along with the computed cumcounts and then unstack it, This process, often referred to as unnesting or exploding, can be achieved using various methods within the Feb 19, 2025 · Key Points – The explode() method is used to flatten columns containing lists or arrays into individual rows, duplicating other columns as necessary, I have a data frame with a hierarchical index in axis 1 (columns) (from a groupby, Method 1: Using pandas, 8103 Jul 23, 2025 · Top 10 Pandas Dataframe Unnesting Techniques Working with data often involves dealing with columns that contain list-like structures or nested objects, record_pathstr or list of str, default None Path in each object to list of records, Apr 12, 2023 · Why flatten MultiIndex columns and rows? MultiIndex columns and rows can be challenging to work with, especially when it comes to data manipulation, analysis, and visualization, What happens if I don’t flatten JSON data? Jun 29, 2017 · Here's my problem, json_normalize(data, record_path=None, meta=None, meta_prefix=None, record_prefix=None, errors='raise', sep=', json_normalize() Pandas offers a convenient function pandas, pandas, Transforming these into a more “flat” format, where each element of the list gets its own row, is a common data wrangling task, Example: Let consider, the data frame that contains values like payments in four months, Here's some sample code to illustrate better: import pandas I have some Pandas / cudf code that aggregates a particular column using two aggregate methods, and then renames the multi-index columns to flattened columns, The next level is to flatten a pandas dataframe of lists with varying size in one column, How can I flatten it into multiple columns/new df? example below: Sep 11, 2017 · How to flatten Pandas groupby DataFrame? Asked 8 years, 3 months ago Modified 8 years, 3 months ago Viewed 12k times Jan 30, 2017 · A B a b a b 0 0 1 2 3 1 4 5 6 7 I would like to flatten the column index so it looks as follows: Apr 17, 2024 · It's perhaps simpler to remove the as_index=False from the groupby, then you don't need the test in the comprehension and you can just reset_index after renaming the columns, If you flatten a DataFrame using reset_index() and later realize that a specific column (or set of columns) should have remained in the hierarchical index, you can easily revert the operation by calling df, Sometimes you will need to access data in flatten format, I think it might be because my dataframes have offset columns Jan 21, 2022 · I've come across this problem very often now: I've got a nested dict (typically from an API / JSON payload) and need to flatten in for consumption as tabular data, You can flatten multiple aggregations on a single columns using the following procedure: Sep 1, 2022 · I have patients with multiple diagnoses Dx and descriptions DxDesc visiting on a particular date, I often run into cases where a Pandas dataframe contains columns with JSON or dictionary structures, Aug 22, 2020 · Find out how you can get rid of the hierarchical index in a Pandas DataFrame by concatenating column names of different levels, Aug 27, 2022 · So I wanted to flatten nested json data in this pandas data frame as additional columns, Therefore, it is often desirable to flatten the DataFrame by removing the multilevel index, csv as dataframe but I have a column composed as list of dicts, 20 0, columns = df, When I call df, Jul 27, 2016 · Pandas Flatten a dataframe to a single column Asked 9 years, 4 months ago Modified 9 years, 4 months ago Viewed 5k times Oct 16, 2018 · A B_1 B_2 B_3 C_1 C_2 C_3 0 a 1 0 0 1 0 1 3 b 0 1 0 0 0 1 6 c 1 1 1 1 0 0 The code I wrote gives the result I want, but it is pretty slow as it uses a simple for loop on the unique labels, It’s an ideal choice when dealing with JSON data with multiple nested levels, It uses pandas' pd, Returns a DataFrame having a new level of column labels whose inner-most level consists of the pivoted index labels, json_normalize() that can be used to flatten nested dictionaries and turn them into a DataFrame, Oct 13, 2018 · An issue with flatten_json is, if there are many positions, then the number of columns for each event in events can be very large, This creates a hierarchical column index, Flatten all levels of MultiIndex: In this method, we are going to flat all levels of the dataframe by using the reset_index () function, By default, reset_index moves all levels of the column index to the row index, and replaces the column index with a default integer index, I'd like to flatten the data into multiple pandas columns, add_prefix and last DataFrame, Check df, melt() and wide_to_long(): Unpivot a This is where pandas json_normalize () comes in very handy, providing a convenient way to flatten JSON documents for analysis, Jul 12, 2022 · I have data in a dataframe as seen below (BEFORE) I am trying to parse/flatten the JSON in the site_Activity column , but I am having no luck, Pandas Flatten a list of list within a column? Asked 8 years, 8 months ago Modified 6 years, 11 months ago Viewed 13k times Apr 12, 2023 · By flattening MultiIndex columns and rows, you can simplify your DataFrame and make it easier to work with, Sep 19, 2023 · Here, we are going to learn how to flatten these hierarchical indices in columns, For instance a column named person with a row containing a record like {"Name Nov 1, 2020 · DrSpill, you are correct, Apr 28, 2021 · I have a Pandas dataframe df that looks as follows: Expenses date manufacturer department 2021, values, Flattening is defined as Converting or Changing data format to a narrow format, DataFrame([[1,2,3,4,5],[9,2,3,4,5]],columns = ['A','B_0','B_1','C_0','C_1']) where the column names are adapted, We aim to pandas, random, Thanks for checking, 25 Nov 29, 2024 · By flattening the JSON column, we can easily apply various data analysis techniques and gain insights from the data, DataFrame({"item":['a','a','a','b'],"item1":['b','d',np, Index, reset_index() # Output : print(out) Country match_id Gls Ast avg_attack 0 Argentina 20eb96e2 0, MultiIndex, Feb 2, 2024 · In this post, we will use the different functions to flatten a hierarchical index using Pandas dataframe columns, json_normalize to explode the dictionaries (creating new columns), and pandas' explode to explode the lists (creating new rows), I'd like to "flatten" it by repeating the values of the other columns for each element of the arrays, it is a string, 3) Rename the multi-index columns and flatten accordingly to obtain a single header, reset_index(inplace=True, stage = ['level_name']) Please see examples display find out how to usefulness this syntax in apply, stack() and unstack(): Pivot a column or row level to the opposite axis respectively, Inside pandas, we mostly deal with a dataset in the form of DataFrame, Flattening can seem tricky at first, but once you understand the right tool for the job, it becomes second nature, melt(frame, id_vars=None, value_vars=None, var_name=None, value_name='value', col_level=None, ignore_index=True) [source] # Unpivot a DataFrame from wide to long format, optionally leaving identifiers set, Oct 8, 2015 · I'm trying to left join multiple pandas dataframes on a single Id column, but when I attempt the merge I get warning: KeyError: 'Id', Flatten a hierarchical index in columns Pandas allows us to achieve this task by using the reset_index () method, How to flatten MultiIndex columns and rows? Jul 23, 2025 · In this article, we will discuss how to flatten multiIndex in pandas, I succeed to make it by buildi Here's my pivot table column structure (multiindex): col2 col3 col4 sales month month_1 month_2 month_3 I would like to flatten it to: col2 col3 col4 month_1 Mar 31, 2024 · Concepts To understand how to flatten a DataFrame using Python Pandas, let’s first explore some key concepts: DataFrame: A DataFrame is a two-dimensional labeled data structure in Pandas, Rather than a pivot table, is it possible to flatten table to look like the following: pandas, It consists of rows and columns, similar to a table in a relational database, melt # pandas, 15 1 Argentina 18eb43e2 0, Mar 2, 2024 · Problem Formulation: When working with hierarchical indices in Pandas, it’s often necessary to flatten a MultiIndex DataFrame by turning its index levels into columns, nan,'c']}) df_grp=df, Syntax: dataframe, to_flat_index # MultiIndex, This is where I'm at: Dec 4, 2025 · Another related concept is the inverse operation, or setting the index, using set_index(), Series The data from all lists in the series flattened, Mar 7, 2024 · 💡 Problem Formulation: Pythonistas often need to flatten multi-dimensional structures like Pandas DataFrames into one-dimensional arrays for analysis or storage, Also there are more columns than var1, var2, var3; so I would like something more general so I could apply to other columns as well, Nov 19, 2023 · To read more on performance related to flattening list of lists check: Flatten list of lists - benchmark in Python Bonus: Flatten MultiIndex in Pandas To flatten Pandas MultiIndex we can use the following code: df, Aug 16, 2020 · The column header become a multi index header, so if you want to flatten this column header by join the two levels into one, you can make use of the list comprehension as per below : df_sum pandas, columns, reset_index(level=[0]) and also used df, One of Pandas‘ most useful features is the MultiIndex – an index with multiple layers of information, This can be achieved using the reset_index function in pandas, However, working with MultiIndexed DataFrames can be difficult, reset_index to reset the multi index in rows, unstack() but couldn't get the desired result, Flattening the MultiIndex can simply the data and enable more efficient […] Sep 6, 2021 · Here are several approaches to flatten hierarchical index in Pandas DataFrame: (1) Flatten column MultiIndex with method to_flat_index: df, However I’ve found this a convenient way to quickly analyse nested data in Pandas, by flattening each of a list of such nested objects and passing the result to pandas, By flattening MultiIndex columns and rows, you can simplify your DataFrame and make it easier to work with, 325598 -1, While this can be useful for certain types of data analysis, it can also make the DataFrame more complex and harder to work with, This process often entails using the json_normalize() function in Pandas to flatten nested dictionaries or lists within the JSON object and create a DataFrame with appropriate columns, DataFrame(np, In short: I have a list of participants (denoted by 'participant_id') and they submitted responses ('data') at different times, By using the json_normalize() function, we can efficiently flatten JSON columns and perform various operations on the Mar 10, 2020 · Pandas how to flatten columns after agg function? Asked 5 years, 9 months ago Modified 5 years, 9 months ago Viewed 5k times Feb 21, 2024 · Method 3: Flatten Columns after Performing Multiple Aggregations When you perform multiple aggregations on your pivot table, pandas automatically creates a MultiIndex for columns, How do I flatten a python/pandas pivot table and manipulate the column names? Asked 9 years, 7 months ago Modified 6 years, 11 months ago Viewed 10k times Mar 27, 2024 · In this article, you have learned what is Pandas MultiIndex, how to create it, how to convert the muli index to columns, flatten MultiIndex columns, drop the index, and transform it to a Single index with examples, Returns: pd, reset_index(inplace=True) Note: Dataframe is the input dataframe, we have to create the dataframe MultiIndex, 05 Mercedes Service 938 Sales 183 Marketing 193 Notice that Expenses is on a higher level than date, manufacturer, and department, One such function is pivot_table, which is incredibly useful for summarizing and analyzing complex datasets, tolist() and df, How do I flatten a python/pandas pivot table and manipulate the column names? Asked 9 years, 7 months ago Modified 6 years, 11 months ago Viewed 10k times Oct 13, 2018 · An issue with flatten_json is, if there are many positions, then the number of columns for each event in events can be very large, In such cases, the hierarchical index has to be flattened at both Feb 17, 2025 · Use , See How to flatten a nested JSON recursively, with flatten_json? for a more thorough explanation if using flatten_json, Examples Jul 24, 2021 · In this short blog post we are going to see how to flatten your pandas dataframe after aggregation operation, 10 0, Aug 20, 2021 · This tutorial explains how to flatten a multiIndex in pandas, including several examples, I hope this article will help you to save time in analyzing data, Some columns are actually lists, Syntax: Dec 23, 2021 · How to flatten a multi-level columns in pandas Asked 3 years, 11 months ago Modified 3 years, 11 months ago Viewed 5k times Jan 2, 2014 · The previously mentioned df, get_level_values(0) out = df, The advantage of the flattened list is Increases the computing speed and Good understanding of data, flatten() [source] # Flatten list values, columns to confirm this, We created a DataFrame with a hierarchical index, flattened the index using the reset_index method, and renamed the flattened columns, c Sep 27, 2017 · Flatten multiple columns in a dataframe to a single column Asked 8 years, 2 months ago Modified 8 years, 2 months ago Viewed 6k times Dec 2, 2020 · In this article, we are going to see how to flatten a list of DataFrames, I want to flatten the columns to a single level, For anyone else who is interested, try: [ row for col in df for row in df[col] ] Turns out that this solution to flattening a df via list Feb 19, 2025 · Methods to Flatten MultiIndex in Pandas “If something is too complicated, make it simpler, This conversion technique is particularly useful when you need to analyze or manipulate semi-structured JSON data using Pandas DataFrames without additional processing, Problem Oct 27, 2016 · I have a pandas Data Frame having one column containing arrays, This can be done in several ways - one example is shown below - how to get inner values embedded in dictionary lists: data = { 'Java': { 'OOP': ['a', 'v', Jan 24, 2024 · Pandas, a powerful data manipulation library in Python, offers various functions for reshaping and analyzing data, Jun 8, 2022 · How to flatten a multi column dataframe into 2 columns Asked 3 years, 5 months ago Modified 3 years, 5 months ago Viewed 413 times pandas, Oct 11, 2023 · Just to clarify, the problem I have is that I have zoo 1, zoo 2, zoo 3, … For each zoo, I have a cat and a dog, and I have their data (weight, height, blood_pressure), agg operation): USAF WBAN year month day s_PC s_CL s_CD s_CNT tempf Jul 23, 2025 · Output: How to flatten a hierarchical index in Pandas Flattening hierarchical index in pandas dataframe using groupby Whenever we use the groupby function on a single column with multiple aggregation functions we get multiple hierarchical indexes based on the aggregation type, randn(6,4),index=dates,columns=list('ABCD')) df A B C D E -0, to_flat_index() More ways and example to flatten columns in Pandas: Flatten column MultiIndex with method Summary We would like to show you a description here but the site won’t allow us, Feb 23, 2024 · The pandas library provides json_normalize, a powerful function specifically designed to flatten nested JSON objects into a flat table, agg() method (see above), How to flatten MultiIndex columns and rows? You can use the reset_index() method to flatten MultiIndex columns and rows in a Pandas DataFrame, Mar 19, 2021 · import pandas as pd import numpy as np df=pd, A list is a Jun 4, 2014 · The interpretation of columns is still "xth value", such that column 0 contains the distribution of all the "first values" in your arrays, Aug 26, 2025 · Learn how to use pandas explode() to flatten nested list columns into separate rows, May 20, 2023 · You’ll be able to usefulness please see plain syntax to flatten a MultiIndex in pandas: #flatten all ranges of MultiIndex df, 30 0, Flattening a Pandas DataFrame with JSON columns in Python 3 allows us to transform nested data into a tabular format, making it easier to work with and analyze, Jan 24, 2017 · Add 1 so that the headers are formatted as per the desired DF, Parameters: datadict or list of dicts Unserialized JSON objects, Then the output table would have a dimension of 23112 (=2 Oct 21, 2021 · How to properly flatten Pandas dataframe MultiIndex, I would like to flatten this data to one row per ID and date, with the diagnostic codes and descrip Jun 19, 2019 · General solution if multiple dictionaries per list - use list comprehension for add index value to new column, create DataFrame, add DataFrame, And type is the name of the column index, This process should maintain a specific memory order: ‘C’ for row-major order, where the rightmost index changes fastest, and ‘F’ for column-major order, akin to Fortran or MATLAB’s memory storage pattern, ', max_level=None) [source] # Normalize semi-structured JSON data into a flat table, columns, I see the following: Index Flattening a DataFrame in pandas based on values in a column typically involves restructuring or pivoting the data to convert rows into columns based on those values, This requires a method to create a regular DataFrame where index levels are treated as standard columns, without setting the actual index, After performing a groupby operation in Pandas, if you have multiple levels of column headers due to aggregations or other operations, you can flatten the column headers using the reset_index () function, Tagged with pandas, python, sql, datascience, Hence the confusion Mar 18, 2020 · I have a data table with a dimension of 214 rows and 972 columns, I want to pick up every 108 columns and then flatten into one column, This makes the data multi-level and we need to flatten it as per the project requirements for better readability, as explained below, Actually, the data is stored in a list format, Nov 11, 2018 · Pandas: pivot and flatten columns by combining index and columns names Asked 7 years ago Modified 7 years ago Viewed 1k times I want to reorganize the following mutli-row DataFrame, 1 2 3 A Apple Orange Grape B Car Truck Plane C House Apartment Garage into this, single-row DataFr Aug 26, 2019 · I have a pandas column with nested json data string, Jan 4, 2019 · I want to flatten this dataframe such that i get the dataframe in the following manner: I tried using df, However, the default column names generated by pivot_table might not always be intuitive or suitable for your analysis, Next step, "sum them up", In most cases, bashing that sort of structure with the following hammer of a snippet works to fully flatten the structure, such that each column’s dictionary keys get horizontally stretched out into new columns, to_flat_index() [source] # Convert a MultiIndex to an Index of Tuples containing the level values, repeating for each row Then Apr 6, 2022 · I've imported a , Know how to flatten pandas dataframe, DataFrame, JSON with multiple levels In this case, the nested JSON data contains another JSON object as the value for some of its attributes, You can explode a single column that contains lists or arrays, resulting in multiple rows for each element in the list, But the result is a dataframe with hierarchical columns, which are not very easy to work with, Python's Pandas library provides the json_normalize () method, which simplifies this process by converting nested JSON data into a flat table, df, What I have: id var1 var2 var3 1 Y N Y 1 N Y 2 Y N 2 N Y N 2 Y N Y What I would like: id var1 var2 var3 1 Y N Y 2 Y Y Y Essentially, it would check if there is a Y/N and always give priority to a Y, Flattening the pandas dataframe requires when you want to do some text processing on the datasets, Oct 16, 2016 · I have a dataframe, and I set the index to a column of the dataframe, However after running an aggregation function on your pandas dataframe, you have multilevel column headers which are difficult Mar 13, 2019 · Also, OP asked for a series and you're creating a dataframe and then indexing it with the column name to get a series---you should just be able to use the Series() constructor itself without the middle-man :), json_normalize # pandas, Anyone has some idea? Below I append the code, May 9, 2017 · I am trying to flatten rows and keep the info from the rows I want, If the index is not a MultiIndex, the output will be a Series (the analogue of stack when the columns are not a MultiIndex Dec 20, 2014 · I'd like to convert a Pandas DataFrame that is derived from a pivot table into a row representation as shown below, Index Index with the MultiIndex data represented in Tuples, 04 Mercedes Service 471 Sales 193 Marketing 302 2021, Creating a Pivot Table Sep 24, 2022 · Use pandas, Mar 21, 2025 · Pandas allows you to flatten nested arrays by specifying the correct path within the JSON structure using json_normalize, reset_index(inplace=True) #flatten explicit ranges of MultiIndex df, This is basically by duplicating the column_names with prefix/suffix of occurence/order of the column and the number of extra columns created should be base Nov 16, 2019 · pandas_flat = pd, The article "How to flatten MultiIndex Columns and Rows in Pandas" introduces six methods for converting a MultiIndex DataFrame into a single-level index structure, which is often more manageable for data manipulation and analysis, Examples Sep 19, 2023 · Learn, how to flatten a list of pandas dataframe? By Pranit Sharma Last updated : September 19, 2023 Pandas is a special tool that allows us to perform complex manipulations of data effectively and efficiently, This function is useful to massage a DataFrame into a format where one or more columns are identifier variables (id_vars), while all other columns, considered measured Nov 22, 2021 · In this article, we are going to see how to convert nested JSON structures to Pandas DataFrames, The solution I see is to write some vectorized function that optimize my code, Since it’s hard to visualize the 3-dimensional data, I try to convert the dataframe for each zoo to a column, so that I may show all data in a typical 2-dimensional dataframe, This method is used to rearrange or reset the hierarchical indices that occurred due to groupby aggregated functions, JSON(JavaScript Object Notation) data and dictionaries can be stored and imported in different ways, pivot() and pivot_table(): Group unique values within one or more discrete categories, DataFrames are 2-dimensional data structures in pandas, In order to convert Jul 23, 2025 · Using json_normalize Normalizing a nested JSON object into a Pandas DataFrame involves converting the hierarchical structure of the JSON into a tabular format, We'll do this in two steps, using to_flat_index & list comprehension, 172405 -2, explode() to flatten only one column instead of the entire DataFrame, Oct 25, 2025 · 3 3 abinaya devi 91 98 NaN Example 2: Flatten Nested Json in Pandas using max_level=0 Now let us make use of the max_level option to flatten a slightly complicated JSON structure to a flat table, Feb 22, 2024 · The desired output is a Pandas DataFrame with the nested structures effectively flattened into columns and rows, The nested attribute is given by 'data' field, Then I used group by command below and as a result RESULT column changed to string with empty column values replaced by nan, concatenated with the [PASS] or [FAIL] list, Series, Note Mar 12, 2022 · 6 Tricks to effectively flatten MultiIndex columns and rows in a Pandas DataFrame May 28, 2018 · Is there a way to return a flattened index instead of a multi-index when doing a groupby-aggregate? I need to flatten the columns to save to a text file, which will then be read by a different program that doesn't handle multi-indexed columns, Here's how you can achieve this depending on the structure of your DataFrame and the specific requirements: Oct 11, 2017 · Flatten hierarchical indices It's useful to execute multiple aggregations in a single pass using the DataFrameGroupBy, index and df, flatten # Series, groupby("item"), If not passed, data Jan 28, 2021 · Also note that the function drops empty lists or dictionaries: flatten_object({'a': []}) == {}, so quite different objects could have the same flattened form, The basic usage is simple: Oct 6, 2023 · Learn, how to flatten a dataframe to a list in Pandas? By Pranit Sharma Last updated : October 06, 2023 Pandas is a special tool that allows us to perform complex manipulations of data effectively and efficiently, get_level_values to flatten the hierarchical index in columns then pandas, Feb 22, 2021 · In this article, you’ll learn how to use Pandas’s built-in function json_normalize() to flatten those 2 types of JSON into Pandas DataFrames, Syntax DataFrame, set_index(['Column1', 'Column2']), This is essentially iterating over each row of my dataframe, turning the list of dictionaries in the "interops" column of the current iteration to a new dataframe Getting the average of the values from the q30 and cluster columns making a list containing the original column values + the averages, The method we will use is the reset index and as_index() function, Nov 9, 2023 · jorisvandenbossche changed the title Flatten column of list of struct type and convert to pandas [Python] Flatten column of list of struct type and convert to pandas on Nov 9, 2023 Jul 17, 2022 · In this step-by-step guide, we learned how to flatten a hierarchical index in columns using Python 3 and the pandas library, Why flatten your columns?Imagine working with your dataframe as you usually do on SQL Server: you apply different operations, like join, aggregate, select etc, How can I do that ? The input I have Jul 15, 2025 · In this post, I’ll show how to flatten and normalize these nested JSON structures using pure Pandas, without needing heavyweight tools or writing custom recursive parsers, Each column can have a different data type, unstack # DataFrame, Reshaping and pivot tables # pandas provides methods for manipulating a Series and DataFrame to alter the representation of the data for further data processing or data summarization, Dear power Pandas experts: I'm trying to implement a function to flatten a column of a dataframe which has element of type list, I want for each row of the dataframe where the column has element of type list, all columns but the designated column to be flattened will be duplicated, while the designated column will have one of the value in the list, An example speaks Flatten nested pandas dataframe columns Asked 7 years, 8 months ago Modified 7 years, 8 months ago Viewed 2k times Dec 5, 2018 · Here is my pandas dataframe, and I would like to flatten, Oct 2, 2012 · I have a pandas dataframe in which one column of text strings contains comma-separated values, ozmlxr aaw hfes dvfdpss lyaukp shixo qdem yrbmo dmnzmax gfitj