Pandas sum row with condition Grouping refers to combining identical data (or data Apr 20, 2022 · I think the solution in your answer can be optimized slightly by using numpy. Let's use the same NBA dataset and group the data by both Team and positionto Dec 21, 2020 · The OP wanted the row-sum of all columns whose names matched pattern, so . Setting axis=1 will sum the values in each row. Aug 3, 2016 · One, df. cumsum() method in Pandas is an incredibly useful tool that allows for the computation of cumulative sums across a DataFrame, either column-wise or row-wise. Dec 1, 2022 · This tutorial explains how to use group by with a where condition in a pandas DataFrame, including an example. See DataFrame shown below, data desired_output 0 1 False 1 2 False 2 3 True 3 4 Tru Mar 7, 2013 · The problem I've been having is that I'd like to take a list of strings, check for a value, then sum the count of that string- broken down by user. Master boolean indexing, query(), value_counts() and more with practical US sales data examples. Dec 2, 2021 · This tutorial explains how to sum specific columns in a pandas DataFrame, including several examples. This is equivalent to the method numpy. Parameters: funcfunction, str, list-like or dict-like Function to use for transforming the data. group by & sum on single & multiple columns is accomplished in multiple ways in pandas, some of them are groupby(), pivot(), transform(), and aggregate() functions. sum () function has been used to return the sum of the values. Jun 2, 2022 · The Launch_Year sums are irrelevant. transform(func, axis=0, *args, **kwargs) [source] # Call func on self producing a DataFrame with the same axis shape as self. Aug 23, 2022 · This tutorial explains how to combine rows with the same column values in pandas, including an example. Parameters: axis{0 or ‘index’, 1 or ‘columns’}, default 0 The index or the name of the axis. Let’s consider an example to illustrate this concept: Feb 22, 2024 · Introduction In this tutorial, we’ll explore the DataFrame. By indexing the columns used in your query filters (e. , category_id and region_id), you can reduce query time by 100x or more compared to unoptimized DataFrames. Let's consider a Pandas Mar 5, 2024 · Problem Formulation: When analyzing data with Python’s Pandas library, you may encounter situations where you need to sum specific rows of a DataFrame, based on certain conditions or indices. Whether you‘re cleaning messy datasets, focusing on specific subsets for analysis, or preparing data for visualization, knowing how to efficiently drop rows based on column conditions is an essential skill in your data science toolkit. 3 documentation pandas. Let's explore different ways to apply an 'if condition' in Pandas DataFrame. 0 is equivalent to None or ‘index’. How do I do this in pandas? Jan 18, 2021 · This tutorial explains how to sum the values in a pandas column based on a condition, including several examples. Boolean indexing allows us to select rows based on a condition, and then perform operations on the selected subset of data. Apologies but my downvote got locked in after 2hrs; in future I won't downvote pending clarification. Is there an efficient way with pandas to do this? Mar 5, 2024 · Problem Formulation: The task is to filter rows from a Pandas DataFrame based on a condition applied to the sum of certain values within these rows. Pandas, Python’s powerful data manipulation library, offers multiple ways to compute row sums while excluding specific columns. transform only if match condition by numpy. 5. I can find lots of examples of summing rows that meet a given condition like "> 2", but can't seem to grasp how to iterate over rows to conditionally sum a column based on values in the current row. sum() function returns the sum of the values for the requested axis, In order to calculate the sum of rows use the default param, axis=0 and to get the sum of columns use axis=1. sum () where dataframe is the input dataframe group_column is the column in dataframe to be grouped sum () function is to perform the sum operation Create the student dataframe with 4 columns Jul 19, 2021 · You can use the following syntax to find the sum of rows in a pandas DataFrame that meet some criteria: #find sum of each column, grouped by one column df. Feb 1, 2025 · I need to sum the vesting_value_CAD for each employee, group, and agreement date, where the expiryDate of other rows is greater than or equal to the current row's agreementDate. If func is both list-like and dict-like Aug 1, 2018 · I need to group my dataframe and use several aggregation functions on different columns. DataFrame () Jul 5, 2020 · In Pandas DataFrames, applying conditional logic to filter or modify data is a common task. Register the index at which the condition is achieved and get the correspondent value from Num_authors. For each row, I'd like to count how many times the value Jul 14, 2020 · Pandas cumulative sum starting last row where condition was satisfied Asked 4 years, 9 months ago Modified 4 years, 9 months ago Viewed 957 times How to apply conditional logic to a Pandas DataFrame. We’ve already covered the Python Pandas groupby in detail. In this article, we will explore how to use Pandas to count and sum data with I am new to Python Pandas. If a function, must either work when passed a DataFrame or when passed to DataFrame. This page provides several common examples of how to use replicate the SUMIF function in Python with pandas. Key takeaways: Nov 24, 2024 · Discover effective techniques to sum values in a DataFrame column based on specific conditions using pandas. By leveraging boolean masks, vectorized operations, and dynamic column selection, you can efficiently analyze row-wise risk sums even in large, messy datasets. 3 documentation Additionally, the cummax() and cummin() methods are available for calculating cumulative maximum and minimum. Methods like loc or query can also handle complex conditions. cumsum — pandas 1. Example 2: Grouping by Multiple Columns Grouping by multiple columns allows you to break down the data into finer categories and compute statistics for each unique combination of those columns. There are possibilities of filtering data from Pandas dataframe with multiple conditions during the entire software development. Nov 1, 2020 · Sum all rows of one or multiple columns Sum by column name/label into a new column Adding values by index Dealing with nan values Sum values that meet a certain condition Creating the dataset We’ll start by creating a simple dataset # Python3 # import pandas into your Python environment. groupby ('group_column'). Fruit, Name, (Number) Total df Fruit, Name Speaking of SQL, there's pandasql module that allows you to query pandas dataFrames in the local environment using SQL syntax. 15 hours ago · For sum aggregations on millions of rows with integer condition columns, multi-level indexes are the fastest solution in Pandas. What is Grouping? Grouping a database/data frame is a common practice in every day data-analysis and data-cleaning. Filter Pandas Dataframe with multiple conditions The reason is dataframe may be having multiple columns and multiple rows. cumsum(axis=None, skipna=True, *args, **kwargs) [source] # Return cumulative sum over a DataFrame or Series axis. The data are all the orders from 2 custom Jun 24, 2022 · This tutorial explains how to create a pandas pivot table that displays a sum of values, including an example. sum(axis=0, skipna=True, numeric_only=False, min_count=0, **kwargs) [source] # Return the sum of the values over the requested axis. loc [] attribute. May 26, 2025 · Learn 9 easy methods to count rows with conditions in Pandas. So you can take a look through the article if you’re unsure about how the function works. apply. I would like to return a second column that is the sum of every item in the column with a condition: only those larger than -1. Oct 30, 2025 · Filtering rows in a Pandas DataFrame means selecting specific records that meet defined conditions. 1 day ago · Conclusion Pandas simplifies summing risk factors across multiple columns with conditions, offering a powerful alternative to Excel’s COUNTIF. loc [], . agg is an alias for aggregate. Apr 9, 2024 · This tutorial explains how to filter rows in a pandas DataFrame after using the GroupBy() function, including examples. Jul 14, 2014 · I've been trying to teach myself pandas to do this with but I am not even sure where to start looking. sum() Are there single functions in pandas to perform the equivalents of SUMIF, which sums over a specific condition and COUNTIF, which counts values of specific conditions from Excel? I know that there Pandas sum row values based on condition Hi friends - I am sure this is very simple but I have googled my heart out and can't figure out how to do this. The sum () method is used to calculate the sum of a DataFrame along a specific axis. in this example, I want to have a list [13 - 12, 17 - 15]. index, and apply() with lambda functions. The Pandas DataFrame. sum. sum () doesn't seem to ignore NaN the way the pandas sum () does by default thanks to its skipna=True argument. where: Jan 26, 2022 · Pandas sum over rows using conditional substring of other columns Asked 3 years, 6 months ago Modified 3 years, 6 months ago Viewed 992 times May 30, 2024 · Summing Values in a Column To sum values in a column with a given condition using Pandas, we can leverage the power of boolean indexing. Sep 9, 2019 · Then it accesses the Points_P1 values on the grouped dataframe and apply the cumulative sum function cumsum(), which returns the sum of points up to and including the current row for each group. DataFrames consist of 403 You can just sum and set axis=1 to sum the rows, which will ignore non-numeric columns; from pandas 2. Nov 17, 2021 · Learn how to use Pandas to calculate a sum, including adding Pandas Dataframe columns and rows, and how to add columns conditionally. sum () instead of DataFrame. The sum () method in Pandas is used to calculate the sum of a DataFrame along a specific axis. Jul 11, 2025 · Output: Pandas dataframe. For each row, I want to do a sumproduct of certain columns o Nov 10, 2023 · It is possible to sum columns based on a condition using the SUMIF() function in Excel. import pandas as pd # Now, let's create the dataframe Mar 6, 2021 · In this article, we’ll be conditionally grouping values with Pandas. Notes The aggregation operations are always performed over an axis, either the index (default) or the column axis. If the input is the index axis then it adds all the values in a column and repeats the same for all the columns and returns a series containing the sum of all the values in each column. Two, numpy sums over all elements in an array regardless of dimensionality. Parameters: axis{index (0), columns (1)} Axis for the function to be applied on. This would give me 5 + 7 + 3 = 15. How do I get these sum values and assign them to the rows with corresponding Category and Launch_Year? I need to be able to do this effectively for a large (>5000) number of categories and the year sales columns from 2010 to 2022. Here is an example: Jul 11, 2022 · Given a Pandas DataFrame, we have to sum values in a column that matches a given condition. . isin (), and . May 21, 2025 · Hey there, fellow data wrangler! If you‘ve worked with pandas for any length of time, you know that filtering data is something you‘ll do almost every day. groupby () Method Note : This is just the snapshot of the output, not all rows are covered here. Jun 26, 2025 · How to get pandas count rows with a condition? To count the number of rows that satisfy single/multiple conditions in pandas DataFrame using shape(), len(), df. You might need to sum values in one column only for rows where another column meets specific criteria, or where multiple conditions across different columns are satisfied. , numpy. ) and grouping. Here, I will select multiple columns of DataFrame using the loc [] attribute and then call the sum I have a Series that looks the following: col 0 B 1 B 2 A 3 A 4 A 5 B It's a time series, therefore the index is ordered by time. g. groupby('group_column'). pandas. Next I need to compare the rows with another row that has a specific condition. I am trying to append a new column to a pandas dataframe which sums all values in existing columns only if they are even. Apr 27, 2024 · Pandas, a popular data manipulation library in Python, provides powerful tools for counting and summing data based on specific conditions. Master the art of filtering data with pandas to keep your analyses clean and relevant. Jul 7, 2025 · Add Column to DataFrame using loc [] Moreover, we can add a column to DataFrame based on the values of existing columns using Pandas. Implementing the Sum with Condition function in Pandas To use SUMIF in Python, you can use conditional expressions, like 'df ['A'] > 5', combined with the `sum` method to sum the values that match the condition. Dec 24, 2020 · how to sum rows with condition? (pandas) Asked 4 years, 2 months ago Modified 4 years, 2 months ago Viewed 245 times Feb 25, 2021 · Hello Community, in my dataframe i have three columns as follow: restaurant_id, annee, moyenne_etoile_annee. I used the below code, but get error: IndexError: ('index 2018 is out of bounds for axis 0 with size 27', 'occurred at index 0') Pls SELECT Key1, SUM(CASE WHEN Key2 = 'one' then data1 else 0 end) FROM df GROUP BY key1 FYI - I've seen conditional sums for pandas aggregate but couldn't transform the answer provided there to work with sums rather than counts. In this article, I will explain how to sum pandas DataFrame for given rows with examples. input Price 0 12 1 14 2 15 3 Jun 19, 2023 · The solution The most efficient way to sum values of a row of a pandas dataframe is to use the sum() method with the axis parameter set to 1. For each row, I want to do a sumproduct of certain columns only if column['2020'] !=0. This method sums up the values in each column by default, or along the rows if specified, facilitating quick statistical calculations across datasets. To get around this, we can call mask () with other=0 to override the default value of other=nan. Dec 25, 2024 · Introduction The sum() function in Python's Pandas library is a crucial tool for performing aggregation operations on DataFrame columns. DataFrames consist of rows, columns, and data Jun 10, 2022 · This tutorial explains how to use groupby and count with condition in pandas, including an example. To know more about filter Pandas DataFrame by column values and rows based on conditions refer to the article links. cumsum # DataFrame. Jan 7, 2022 · In this post, we will learn how to filter column values in a pandas group by and apply conditional aggregations such as sum, count, average etc. 0+ you also need to specify numeric_only=True. DataFrame. Jul 23, 2025 · To know more about filter Pandas DataFrame by column values and rows based on conditions refer to the article links. 3 days ago · For example, a dataset might have columns like `GID`, `Math_Score`, `Science_Score`, and `English_Score`, where you want to sum the scores but exclude `GID`. Use the alias Jul 20, 2021 · sum duplicate row with condition using pandas Asked 3 years, 8 months ago Modified 3 years, 8 months ago Viewed 1k times Jan 29, 2022 · I'm trying to figure out how to sum a set of rows based on a condition for each region. sum () function and passing the parameter axis=1 Nov 28, 2021 · I have the below dataframe. sum () function returns the sum of the values for the requested axis. Sep 27, 2022 · This tutorial explains how to sum specific rows in a pandas DataFrame, including several examples. sum () function has been used to return the sum of the Dec 3, 2024 · To sum all Pandas DataFrame rows or given selected rows use the sum() function. The method should be relatively fast since the dataframes in practice will be relatively large, so no for loops etc. mean(arr_2d) as opposed to numpy. This method is essential for performing sum Feb 1, 2024 · This article explains how to count values in a pandas. For Series this parameter is unused and defaults to 0. These functionalities are particularly useful when working with large datasets and needing to extract specific information or perform calculations based on certain criteria. It is for a Series, but the same principle applies: group by n rows (thus not by a specific combination of columns), then sum those groups. merge with right join, so possible create sum s per groups to new column in GroupBy. sum(axis=0); their wording is a bit unclear. cumprod — pandas 1. And some of this aggregation have conditions. For instance, imagine we have a DataFrame with various numerical columns, and we want only those rows where the sum of specific columns exceeds a certain threshold value. Pandas dataframe. So I would like to take this data: May 28, 2019 · @cyrinepersonne the other result Jez calculates row by row, and this one calculates based on the sum of line amount taking id_command as a group. python dataframe sum by row with conditions Asked 8 years, 5 months ago Modified 8 years, 5 months ago Viewed 1k times Mar 27, 2021 · Does this answer your question? Take the sum of every N rows in a pandas series. Here is an example. Through the presented examples, we Jul 23, 2025 · In this article, let's discuss how to filter pandas dataframe with multiple conditions. sum () method in Pandas, an incredibly versatile and powerful Python library used for data manipulation and analysis. Series that meet specific conditions by column, by row, and in total. For Series this parameter Nov 17, 2021 · Learn how to use Pandas to calculate a sum, including adding Pandas Dataframe columns and rows, and how to add columns conditionally. Submitted by Pranit Sharma, on July 11, 2022 Pandas is a special tool that allows us to perform complex manipulations of data effectively and efficiently. for each restaurant_id i would like to substract the "moyenne_etoiles_annee' of the Jun 29, 2023 · For avoid specify many conditions create dictionary for mapping A and B groups, convert to DataFrame and use DataFrame. I need to do a cumulative sum of the data in Num_Albums until a certain condition is reached. odd_lst = [1, 3, 5, 7, 9] even_lst = [0, 2, 4, 6, 8] df = pd. The axis parameter specifies whether to sum the rows (0) or the columns (1). Jul 23, 2025 · The rows consist of different customers and columns contain different types of fruits. Aug 3, 2023 · (2,3): 1+2+12 = 15 (3,4): 0+1+12 = 13 (3,5): 0+1+2 = 3 Basically, I need to sum the Y_ik column on time per row with a condition based on k column. Jan 30, 2015 · Suppose I have a dataframe like so: a b 1 5 1 7 2 3 1 3 2 5 I want to sum up the values for b where a = 1, for example. For example, for the first row (employeeID 2 in group A with agreementDate 2/1/2025), the sum of vesting_value_CAD should be 200 + 40, that is the sum of agreement IDs 7 and 6. Jul 23, 2025 · Pandas dataframe. Using apply () with a Lambda Function We can apply an "if condition" by using apply () with a lambda function. I tried Dec 28, 2020 · I have a dataframe (306x40) with multiple rows containing data of certain group, I need to group them by index, that's no problem. For a minimal example Jun 4, 2025 · Whether you’re filtering rows, creating new columns based on conditions, or conducting boolean indexing, understanding conditional logic in Pandas is essential for efficient data workflows. DataFrames are 2-dimensional data structures in pandas. Python Pandas: How to Sum Column Values Based on Condition (s) Calculating conditional sums in a Pandas DataFrame is a frequent operation in data analysis. Inside pandas, we mostly deal with a dataset in the form of DataFrame. query (). Mar 2, 2021 · My goal is to get all differences of the value of consecutive groups of rows satisfying the condition, i. Nov 17, 2022 · Learn, how to find the conditional sum for a groupby object? Submitted by Pranit Sharma, on November 17, 2022 Pandas is a special tool that allows us to perform complex manipulations of data effectively and efficiently. You can sum multiple columns into one column as a 2nd step by adding a new column as a sum of sums column, df ['total_sum'] = df ['column3sum'] + df ['column4sum'] etc. Could someone please guide me on how to Jul 21, 2021 · how to sum rows in my dataframe Pandas with specific condition? Asked 3 years, 11 months ago Modified 3 years, 11 months ago Viewed 2k times Feb 22, 2024 · The DataFrame. Pandas cumulative sum on column with condition Asked 10 years, 7 months ago Modified 10 years, 7 months ago Viewed 17k times Jun 5, 2024 · Wanted Result: I want to sum row value of a given column (in this case 2030) based on conditions for other columns. For example: when Scenario = Stated, Flow = Total Energy Supply, I want to sum the values of 2030 where Product is Wind and Solar, so in this case, my result would be a new row in which the value on column 2030 is 22. I'm trying to understand how to sum up a subset of rows based on 2 indices in Pandas. DataFrame () 1 day ago · In this blog, we’ll demystify how to use Pandas to sum risk factors across columns with conditions. pandas requires two separate calls to sum one for each dimension. In this guide, we will explore how to apply condition in Pandas DataFrame using various methods, complete with code examples and best practices. Jul 13, 2021 · I know there are some questions on Stack Overflow on Sumproduct but the solution are not working for me. Pandas provides several efficient ways to do this, such as boolean indexing, . Steps needed: Create or import the data frame Sum the rows: This can be done using the . This allows you to apply a custom function row-wise or column-wise to your DataFrame. I am also new to Python Pandas. In this article, I will explain how to count the number of rows with conditions in DataFrame by using these functions with examples. Apr 2, 2023 · In pandas, you can calculate cumulative sum and product using the cumsum() and cumprod() methods for pandas. Jul 23, 2025 · This function is used to display sum of all columns with respect to grouped column Syntax: dataframe. e. Jan 17, 2023 · This tutorial explains how to sum the values in a pandas column based on a condition, including several examples. sum() is a numpy operation and most of the time, numpy is more performant. The first index groups the rows and the second index will determine which rows to sum. mean(arr_2d, axis=0). values. We’ll start with basic single-column "COUNTIF" equivalents, then dive into multi-column scenarios, and explore advanced use cases like handling missing data and dynamic column selection. This filters rows where Region_B > 50 (indices 2, 3), then computes the cumulative sum of Region_A values (110, 110 + 130 = 240). 66 (Solar pandas. DataFrame and Series. Returns a DataFrame or Series of the same size containing the cumulative sum. This function takes three arguments: range, criteria, and sum_range. It's not part of Pandas, so will have to be installed separately. Key Points – The groupby() function is used to group data in a DataFrame based on one or more columns, allowing for aggregation or Sep 15, 2021 · This tutorial explains how to perform a GroupBy sum in pandas, including several examples. You want to filter the data frame on the basis of their purchasing. Feb 19, 2024 · The aggregation is now applied separately to each group, offering insights specific to ‘X’ and ‘Y’ categories: A B C sum mean sum mean sum mean Category X 4 2 14 7 24 12 Y 6 3 12 6 18 9 Conclusion The aggregate() method is a pivotal tool in the Pandas library, offering the flexibility to perform both simple and complex data aggregations efficiently. sum (), but numpy. Pandas sum row values based on condition Hi friends - I am sure this is very simple but I have googled my heart out and can't figure out how to do this. You mean need to do some extra work to get the result back into the same dataframe. Learn how to effectively drop rows in a pandas DataFrame based on specific conditions. The required sums are all there under the year columns. transform # DataFrame. This behavior is different from numpy aggregation functions (mean, median, prod, sum, std, var), where the default is to compute the aggregation of the flattened array, e. loc [] is used to select rows and columns by names/labels of pandas DataFrame. Apr 13, 2017 · 10 how I can sum previous rows values and current row value to a new column? My current output: Jul 11, 2020 · I added some examples above on how to remove the extra row/multi-index with "sum" and "mode". These sums should be in a new column of the dataframe. This is the second episode of the pandas tutorial series, where I'll introduce aggregation (such as min, max, sum, count, etc. For example: Region | Week | Year | value ---------------------------- Jul 3, 2025 · In this article, I will explain how to use groupby() and sum() functions together with examples. DataFrame or pandas. sum # DataFrame. This guide provides step-by-step instructions and code examples to simplify your data manipulation tasks. Apr 12, 2024 · A step-by-step illustrated guide on how to sum the values in a DataFrame column that match a condition in multiple ways. cei ugludzzg dlzhthf uzbgfu pkstr gkmgl ekf izk pqnggi hqzqc atkbed yqzb ynfii uxxjh lgzswp