Dplyr conditional replace values in column table::fifelse () is better and faster. The basic functionality is built defined in coalesce, though, which can be applied programmatically if you don't want to specify lots of column names. Jul 23, 2025 · The dplyr package in R offers a versatile and efficient way to change the value of variables within a data frame. After we find that location we replace the marks with 25. You can handle NA values in case_when() transformations. Conditional Data Transformation In real-world scenarios, it’s common to perform conditional transformations on data. ---This video is based on Apr 7, 2021 · I need to replace values with NA in 50 columns conditional on the value of the column "positive == 0". This is a translation of the SQL command NULLIF. In this guide, I will show you multiple ways to replace values in a pandas DataFrame column based on conditions. ---This video is bas Nov 25, 2020 · As you know, the filter will subset the data frame. Just like the other {tidyverse} functions, mutate work How to replace values at certain indices in a column based on presence of a string in values of that column (using dplyr and repeatedly with no . Here's what I've tried so far using dplyr package. Apr 5, 2022 · I am trying to conditionally replace values in one column/row with values from another column/row using dplyr. We use these conditions to categorize or eliminate value etc, It has a simple syntax syntax: case_when ( X ~ Y) parameters: X: Condition to be applied ~: tilde Y: Value to be set Here x is Apr 15, 2021 · I want to replace values for multiple columns to NA based on the values in the other columns. See example below: wl <- data_frame(x=1:4, multi=c("Y"," Dec 13, 2022 · How to replace values of a character column based on the occurrence of specific strings in another column of an R data frame? Asked 2 years, 8 months ago Modified 2 years, 8 months ago Viewed 1k times Jun 7, 2021 · A simple explanation of how to create new variables in R using the mutate () and case_when () functions. Comprehensive guide covering basic to advanced techniques, optimization, and best practices. In the following data set, I want to replace in columns 3:5 all values of 2 by "X" and all values of 3 by "Y", bu Jul 23, 2025 · Conditionally Replacing Values in a Data Frame Suppose we want to replace all values in the "Department" column with "General" if the salary is below $60,000. This is an S3 generic: dplyr provides methods for numeric, character, and factors. " There are two Jul 2, 2018 · I'm trying to mutate and replace column values with vectors in stringr. If the evaluation timing is important, for example if you're generating random variables, think about when it should happen and place your code in consequence. And also filter on … Feb 4, 2022 · I've been looking at the various answers for similar issues, but can't see anything that quite answers my problem. See full list on sparkbyexamples. frame (x1 = 1:5, date = c ("2020-01-25", NA,… Aug 16, 2021 · And for participant whose UniqueKey == 1484, I want to replace column month value from 79 to 09, and column day to 7. I'm having some issues which I guess is related to how the function recycles. See vignette ("colwise") for details. Summarize Cases Apply summary functions to columns to create a new table of summary statistics. In addition to dplyr, base R also offers versatile methods to achieve the same. In the example below, I want to replace values of displ, cty, why to NA if cyl equal 4. Selecting columns based on specific conditions is common in data manipulation and analysis. NOTE: Because there is a change in @docendo discimus code, I changed 0 to 0L for the data. Nov 14, 2023 · I am having trouble writing a code that would replace all specified values in multiple columns with new values. For example, you might want to categorize ages into groups ("Child," "Adult"), flag outliers in a numeric column, or recode text labels based on a threshold in another variable. data, ) to group data into individual rows. I can mutate them one at a time like this: Dec 6, 2018 · Specifically, if column y3 has value 1 with a row-floor of 2, should that value be marked NA? In the reverse, if column y1 has value 3 with a row-floor of 2, should that value be marked NA? Apr 19, 2022 · I'm trying to conditionally replace values with NA in R. 18 hours ago · In data analysis and cleaning, a frequent task is modifying variable values based on conditions defined by other variables. To this end, as for ggplot, in dplyr, quotation marks for the column names of Lookup and replace column values using dplyr in r Asked 7 years, 9 months ago Modified 7 years, 9 months ago Viewed 4k times Summarise Cases These apply summary functions to columns to create a new table of summary statistics. Like that replace with multiple conditions, how can I achieve that? Thanks a lot. loc [] Function The dataframe. Nov 15, 2024 · Let's explore different methods to replace values in a Pandas DataFrame column based on conditions. There are three variants: _all affects every variable _at affects variables selected with a character vector or vars () _if affects Learn how to easily replace multiple values in a data frame using dplyr in R, specifically when working with conditional selections. to specify the original column Just a heads-up about this: funs() are going to be deprecated in near future - soft deprecate funs () by romainfrancois · Pull Request #3930 · tidyverse/dplyr · GitHub. Let’s select specific values in the ‘cyl’ column and replace them with 99: ## cyl ## Mazda RX4 6 Jul 13, 2022 · The post How to do Conditional Mutate in R? appeared first on Data Science Tutorials How to do Conditional Mutate in R, It’s common to wish to add a new variable based on a condition to an existing data frame. May 27, 2016 · Is it possible to restrict a data frame to a specific row and then change some values in one of the columns? Let's say I calculate GROWTH as (SIZE_t+1 - SIZE_t)/SIZE_t and now I can see that there Jun 13, 2022 · How can I replace values of multiple columns based on one or two conditions below # replace values of multiple rows based on one and two column data <- data. if or modify would only realize if we allow the function to directly modify the underlying data by reference (as is done by data. You understand how to keep the default values of a variable in a case_when() formula You can write case_when() conditions involving multiple Dec 7, 2016 · I am trying to replace a value (e. Mar 13, 2022 · Hi gueyenono, Thank you very much for your help. frame ("Col1" = letters [1:6], "Col2" = 1:6) > d My first thought is to tidy the data with pivot_longer () from dplyr so the colname is also a value, write a little function that takes the colname and value as arguments and map (from purrr) over them to replace the value. table` May 10, 2021 · I am hoping to use dplyr on d1 to find the shared columns, and replace their values with those found in d2, matching on ID. 9. Jul 28, 2020 · tidyverse and dplyr: Conditional replacement of values in a column based on other column [duplicate] Jun 27, 2022 · This tutorial explains how to replace multiple values in a data frame in R using dplyr, including an example. These techniques are essential for data cleaning May 4, 2022 · I try to conditionally replace multiple values in a data frame. In R, the dplyr package offers efficient functions for data manipulation, including mutate () for creating new variables with modified values and case_when () or recode () for replacing multiple Nov 16, 2021 · This tutorial explains how to replace values in a data frame in R based on specific conditions, including several examples. frame s constrain a column vector to be the same data type. This is my code, it does not work at all. 2 Learning objectives You can transform or create new variables based on conditions using dplyr::case_when() You know how to use the TRUE condition in case_when() to match unmatched cases. I have spent quite some time now to figure out how to apply this mutate function to other columns without having to reproduce the command 50 times - to no In a large dataframe ("myfile") with four columns I have to add a fifth column with values conditionally based on the first four columns. frame (id = 1:3, gender = c ("Female", &q These functions provide a framework for modifying rows in a table using a second table of data. This process is often necessary to standardize or clean the data before analysis. I have achieved the task using the following approaches. Aug 19, 2024 · How do you select data frame columns by the condition in R? You can use the select_if() function from the dplyr package to select columns based on their types. Note that when a condition evaluates to NA the row will be dropped, unlike base subsetting with [. See tidyr cheatsheet for list-column workflow. Oct 20, 2017 · Conditionally replace the values in columns to value in another column using dplyr Asked 7 years, 8 months ago Modified 1 year, 7 months ago Viewed 3k times May 20, 2018 · I have tried mutate_at and replace_na and some ifelse statements but I just cannot seem to figure out how to correctly do it. Method 1: Replacing value based on a Single condition We replace values in a column when a single condition is true. In this article, we mutate() creates new columns that are functions of existing variables. I'm looking to find a simple way to do something like the following but with dplyr, essentially just replacing the values in 3 columns with NA when the condition is met. Jan 12, 2019 · A follow-up from a previous question How to select all columns based on a type, with the exception of one column based on a select helper function? Use rowwise(. Explore how to conditionally replace values in a dataframe column using R and the `dplyr` package, for cleaner and more efficient data manipulation. Example 1: We will replace values in the age column where age == 24. Inside across() however, code is evaluated once for each combination of columns and groups. The second var the input column and the third var specifies the column to use in the conditional statement you are applying. Oct 29, 2018 · When you use these scoped variants, you wrap the mutation function inside funs() , and then you have access to . I am looking for a way to conditionally replace certain values in a subset of columns with that column name staying in the tidyverse. If you want to apply that operation to multiple columns, see across. Pandas makes this process easy, offering several methods to accomplish this task efficiently. Dec 18, 2019 · I want to use the pipe function of dplyr package to change values of a column conditionally. The mutate () and case when () functions from the dplyr package make this task fortunately simple. It is worth noting that you can't combine the string "all" with a numeric value like 300, since Rdata. This function allows for the creation of new columns or the modification of existing ones based on a specific condition. Jun 27, 2022 · This tutorial explains how to replace a string in a specific column of a data frame using functions from the dplyr package in R. mutate with an ifelse is probably what you want. g. Here is a sample of the data: Jul 24, 2021 · I have a data frame where the "Threshold" column is based on the values in the first 4 columns. I end up with the following code, but I can't figure out how to refer to the original value from the column (if it shouldn't be replaced). Let's explore how to recode values using dplyr. So in the tibble df below, I want to multiply all values in the columns agr, The recode() function offers a flexible and explicit mechanism for mapping old values to new values. Jun 14, 2021 · This tutorial explains how to replace particular values in a data frame in R, including several examples. May 14, 2014 · Addition: Probably most of the potential speed gains of a separate function replace. Dec 2, 2024 · To add a new column to a data frame in R based on single or multiple conditions, you can use the mutate() function from the dplyr package. So I changed the strength variable in df1 to be a character vector, instead. Arguments data A data frame or vector. ---This v Jan 16, 2018 · dplyr mutate using conditional column and specific rows Asked 7 years, 8 months ago Modified 7 years, 8 months ago Viewed 7k times Sep 17, 2019 · I have a tibble in R, where I want to change values in some columns with a condition based on a value of another column. I have figured out how to replace values in a single column conditionally with mutate. 5 Manipulating data with dplyr The dplyr package, part of the tidyverse, is designed to make manipulating and transforming data as simple and intuitive as possible. Prefer answers with dplyr and mutate, mainly because of its Timing of evaluation R code in dplyr verbs is generally evaluated once per group. However, if there is a "Yes" In the Hotspot Column, I want to replace the Threshold value as being "High". The dplyr package provides the tools to execute these transformations with precision. The content of the article looks like this: Feb 17, 2025 · Learn how to efficiently replace values in R data frames using lookup tables. The syntax is dataframe %>% replace_all (list (old_value1 = new_value1, old_value2 = new_value2)). The column index for the replacement is given in column j . For even more complicated criteria, use case_when (). You can still use exactly the same approach, but your functions need to be Jan 2, 2019 · Can someone help with the following please? In the code below, I want to do the following: Filter on ID 3 and then replace the NA value in the 'Code' column with a value, lets say in this case "N3". The scoped variants of mutate () and transmute () make it easy to apply the same transformation to multiple variables. loc [] function allows us to access a subset of rows or columns based on specific conditions, and we can replace values in those subsets. However, if I want to keep the whole data frame and modify part of it, besides the base method dataframe[condition, "column"] <- values, how could I achieve this using dplyr? I found some good solutions from here as follows: mutate + ifelse suppressMessages(library(dplyr)) Mar 12, 2022 · Change values in a variable based on a conditional value in R Asked 3 years, 4 months ago Modified 3 years, 4 months ago Viewed 2k times Mar 13, 2015 · I would like to simultaneously replace the values of multiple columns with corresponding values in other columns, based on the values in the first group of columns (specifically, where the one of the first columns is blank). A guiding principle for tidyverse packages (and RStudio), is to minimize the number of keystrokes and characters required to get the results you want. This is called replacing values based on a condition. Mar 27, 2024 · Replace column values based on checking logical conditions in R DataFrame is pretty straightforward. Yet, I guess that having a function that allows fast modification by reference of an Jul 21, 2025 · In R programming language, we can change (replace) certain values in a dataset only when a condition is true. Jan 13, 2015 · At the request of @docendo discimus, benchmarking again his "new" version of dplyr using data. It is useful if you want to convert an annoying value to NA. x2 and x3: 1473. rows_insert() adds new rows (like INSERT). Learn how to easily replace data in a column with values from another column based on specific conditions using the `dplyr` package in R. We might need to change the order of factors, create new variables based on other columns in the data, or even variables conditional on specific values in other columns. Any explanations or creative solutions are welcome. I don't know how far this is consistent with the current philosophy of dplyr functions. Also apply functions to list-columns. Mar 7, 2022 · I want to apply 2 conditions: If X1 = 1 then replace its corresponding value in X2 by YES If X1 = 2 then replace its corresponding value in X2 by NO Leave all the other values unchanged, keep the original values in X2 I wanted to use the "replace" function with "case_when" for this but I did not find a solution. 4. The filter() function is used to subset a data frame, retaining all rows that satisfy your conditions. Replace Values Using dataframe. recode () is a vectorised version of switch (): you can replace numeric values based on their position or their name, and character or factor values only by their name. Unlike traditional base R methods that often require indexing or complex conditional logic, recode() allows for simple, direct specification of the desired level changes. table_1. Summary functions take vectors as input and return one value (see back). I used below approach - library (dplyr) > df = data. Scoped verbs (_if, _at, _all) have been superseded by the use of pick () or across () in an existing verb. 0. If data is a vector, replace takes a single value. If you are using a multiple comparission a dplyr::case_when () is a good option to map values from one column based om another ome however if you are using a uniqu condition the data. 12. Jul 28, 2018 · If the lookup table is more than two columns, it's an update join, which doesn't exist in dplyr (for now). Thank you again. By default, key values in y Aug 26, 2021 · It does not apply a conditional statement to the individual elements in a column. 5 and dplyr_0. Data manipulation is an essential step in data analysis, and creating new columns based on specific conditions is a frequent task in the R programming language. We can use replace to change the values in 'mpg' to NA that corresponds to cyl==4. A function missing one of these would have to assume (hard-code in) one or more of these [input, output, conditional column]. Nov 27, 2018 · Given the following data frame: df <- data. Whether you need to modify single variables based on specific conditions, update multiple variables simultaneously, or apply transformations across multiple columns, dplyr provides intuitive functions such as mutate (), transmute Aug 31, 2020 · Replace values in one column condition on another column: R Asked 4 years, 8 months ago Modified 4 years, 8 months ago Viewed 685 times Sep 11, 2025 · Two types of Conditional Mutate in R: case_when () ifelse () case_when () function in mutate () case_when () is a function used in mutate () to create and modify the columns of a dataset using conditions. Dec 26, 2023 · ## XI. Mar 8, 2021 · 0 This question already has answers here: How to replace NA values in a table for selected columns (12 answers) Mar 6, 2025 · I've tried a few other versions, but the problem always seems to be with referencing another column within the replacement value for case_when(). Jun 20, 2017 · I would like to replace the values c t, o p of the column b with c_t, o_p respectively. To be retained, the row must produce a value of TRUE for all conditions. This function takes two arguments, the name of the data frame and a list of the values to be replaced. Update a Value in One Column Based on Criteria in Other Columns Asked 10 years, 9 months ago Modified 6 years, 3 months ago Viewed 119k times Motivation Often, the data we have do not contain exactly what we need. always 1) in a specific column of a dataframe. Learn how to efficiently replace specific values in a data frame column using `dplyr` in R by checking conditions in another column. com Jul 23, 2025 · Replacing multiple values in a data frame involves substituting specific values in one or more columns with new values. Dec 27, 2022 · The dplyr function mutate in R might be one of the most popular functions that are used, for example, by creating a new data frame column. table). I have a large data table Number_X Amount 1 100 2 100 1 100 3 100 1 100 2 100 I wa Jul 15, 2020 · Here is one way to do this using some functions from the {dplyr} package. Feb 17, 2023 · This tutorial explains how to use the mutate() function in dplyr based on multiple conditions, including examples. Each value in replace will be cast to the type of the column in data that it being used as a replacement in. dplyr functions will compute results for each row. frame("a" = 1:5, "b" = 2:6, "c" = 3:7, "d" = c(NA,1,1,0,0)) How can I change values in columns a, b, and c to NA if values in column d are either NA o Feb 21, 2023 · This tutorial explains how to filter for rows that contain a value in a list using the %in% function in R, including an example. Jan 25, 2017 · Since it's unclear how you'd like to replace missing values, I replace them using mean imputation (taking the mean of the column and using that to replace the value). All you need to do is select the column vector you want to update and use the condition within []. Data have <- data. Nov 3, 2023 · Using the dplyr package, it is possible to replace multiple values in a data frame by using the replace_all () function. There's plenty of examples of replacing values in a single vector of a data frame in R with some other value. ---This video is based on The mutate () function is a powerful tool in R for adding new columns to a data frame, or for modifying existing columns. The functions are inspired by SQL's INSERT, UPDATE, and DELETE, and can optionally modify in_place for selected backends. Jun 16, 2021 · This problem is hard to express in a title line, but it is a different question than the usual "how do I change the value in one column based on a value in another column. It can be used to perform a variety of conditional operations, such as adding a new column that indicates whether a value is greater than or equal to a certain threshold, or replacing all values in a column with a new value if a certain condition is met. May 14, 2024 · This tutorial explains how to replace values in a data frame in R based on a lookup table, including an example. The two tables are matched by a set of key variables whose values typically uniquely identify each row. replace If data is a data frame, replace takes a named list of values, with one value for each column that has missing values to be replaced. May 21, 2025 · When working with data in Python, I often encounter situations where I need to replace values in a DataFrame based on specific conditions. The data frame has 20+ columns and I only want to change values in 8 columns (col1, col2, col3, etc). The `dplyr` package, part of the tidyverse, is the gold standard for this in R due to its Mar 18, 2022 · How to change values of a data frame column using the dplyr package in R - R programming example code - R tutorial - Extensive info Jul 21, 2025 · In R programming language, we can change (replace) certain values in a dataset only when a condition is true. So basically I am trying to replace all NA values in column Occupation based on three conditions and then once those three conditions have been met, replace with the work retired. Columns: Rows: (These determine the number of problems) Level 1: one (usually) or two operations, one (usually) or two variables. Replace Values in Data Frame Conditionally in R (4 Examples) In this tutorial, I’ll show how to exchange specific values in the columns of a data frame based on a logical condition in R. Adding new variables, In {tidyverse}, when we add new variables, we use the mutate() function. I just want to replace "X" values in column x2 by values of the same rows of column x3 of the data frame. It can also modify (if the name is the same as an existing column) and delete columns (by setting their value to NULL). I'm new to R and can't seem to figure out exactly Oct 11, 2021 · Is there a way to assign the value of the column being created using an existing value from another column when using case_when() with mutate()? The actual dataframe I'm dealing with is quite compl Jul 23, 2025 · Recoding values is a common task in data analysis, and the dplyr package in R Programming Language provides a straightforward way to achieve this using the mutate () function along with other functions like case_when () or recode () from the dplyr package itself or if-else () from base R. Replace a value in a data frame based on a conditional (if) statement in R replace numbers in data frame column in r [duplicate] And also how to replace all values of NA with something else: Apr 30, 2024 · To replace these NA values with zero, the mutate () function from dplyr can be used. Oct 26, 2021 · This tutorial explains how to replace the values in a column of a pandas DataFrame based on a condition, including several examples. ccqtkwy ffbwtcv wqxdcpto eeywv kgvmv ptwldxq zywwgo lhcc blbkc wlyo txuc kilz yxino uqlwv icbi