R dplyr mutate if column exists. Mutate by condition with many columns with each one a different setting. The rename() function in dplyr is particularly useful when dealing with datasets that have columns with unclear or Nov 17, 2023 · Grouping columns and columns created by are always kept. Apr 5, 2020 · I am trying to mutate 3 columns into 3 new columns in a larger table (with more columns). However, the following works: Why do you want to do this in ways that are not supported. a = c(1,2), b = c(1,2), c = c(1,3) While exists is primarily used to check for variables in environments, it can also be used with data frames and lists because they can store named objects. Aug 12, 2020 · For instance, here, columns a, b, and c are either added, subtracted, or multiplied together, based on column name. This is just two more ways to do exactly what the solutions in the question did: call the function and pass it a second argument inside mutate(). 4, featuring: two new functions if_all() and if_any(), and improved performance improvements of across(). Jul 28, 2022 · mutate(cum = get_sum(x = . r What I did is imaped over the columns of the data frame. Then add a tibble data frame that has the same number of columns as the column names (i. How to keep and remove columns with certain Dec 20, 2023 · The mutate function from the dplyr package allows you to create new variables or modify existing variables in a data frame or a tibble in R. For each unique value of A for which all of these conditions hold true, then E = 1, else E = 0. Dec 27, 2022 · Here are 8 examples of how to use dplyr mutate in R. In order to recive a donut (coded 1) requires a score of at least 3 (or more) for: at least one of "a" criterion items, at least two of "b" criterion items and at least three of "c" criterion items. x Column a doesn't exist. our desired output is this, which creates a new column with NA values if the original column does not exist: > my_df aa bb c 1 1 4 NA 2 2 5 NA 3 3 6 NA Aug 28, 2021 · But if the field doesn't exist, an error: mtcars %>% rename(MPG = mpg, CYL = cyl, bla = uyhgfrtgf) Error: Can't rename columns that don't exist. Technically, mutate and similar dplyr verbs can accept an unnamed expression, where the return value of that expression returns a data. Jun 22, 2018 · I know it's a strange data set and that the columns have data of varying types. funs is an unnamed list of length one), the names of the input variables are used to name the new columns; Vectorised if-else. Oct 7, 2017 · Removing columns names is another matter. Aug 25, 2022 · You can use the following methods to check if a column exists in a data frame in R: Method 1: Check if Exact Column Name Exists in Data Frame. The . Say I want to create a conditional variable that returns a hit every time any row in a data frame has a column that contains the target. R - dplyr - mutate_if multiple conditions. df &lt;- data. This may actually work best in my implementation since I'm working with dplyr and have a line creating the valid column already. To create a tibble that contains NA automatically (Thanks to the comment by Darren Tsai) Nov 1, 2015 · The only way I can justify "dplyr" here is if you include the conversion of the first column to "character". Whereas I want to mutate based on a corresponding value in a column outside Sep 25, 2016 · I believe you can use length and which to count the number of occurrences for which your condition is true for each id in df1. R. Nov 23, 2021 · Stack Overflow Public questions & answers; Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Talent Build your employer brand Aug 21, 2020 · Often you may want to create a new variable in a data frame in R based on some condition. Thanks for the edit, @Axeman. The following R programming syntax shows how to use the mutate function to create a new variable with logical values. " Mutate: Change or Create Columns. While it is a bit more verbose than the Base R approach, the logic is at least more immediately transparent/readable. g. If not, they'll create one with value 0. three columns, in this MWE) to the original data frame (i. 0. "used" retains only the columns used in to create new columns. In this example, I have a simple data. Oct 27, 2022 · R mutate multiple columns with if statement. e. Feb 12, 2018 · You can use the one_of() select helper from dplyr and pass the column names as strings. I do this by supplying a logical vector as predicate. - A)) The . 3 of the new columns depend on first existing 3 columns. df %>% mutate_at(. Apr 27, 2020 · mutate(isAnyType = any(typ1, typ2, typ3)) seems to be using the whole columns, when I would like to use the information per row. the readability of @akrun answer is very straight forward. 3, dplyr will keep the existing columns unchanged and create new columns in this approach. ) should make no sense in it. 2. The second option of code under each output uses case_when which is easier to write and understand. x Column `uyhgfrtgf` doesn't exist I looked at ?rename_if and it says this is now superseded by rename_with(). But why does Code 2 work fine without the ~ symbol in front of names(. S. I want to store the mapping as follows and use it to build the above logic May 3, 2019 · In general, you just need to do a bit of math/algebra to translate to a non-iterative definition (though this might not always be possible). mutate(new_col=c(1, 3, 3, 5, 4), Jan 12, 2019 · Thank you @divibisan, this is very helpful. The names of the new columns equal the names of the named vector you create in advance (vars in this case). Apr 23, 2019 · I'm trying to populate one column with the values in the same row in another column, where I have missing values. if it will only loop over the columns that exist in the data. A data frame or tibble, to create multiple columns in the output. 4 you really should use if_any or if_all, which specifically combines the results of the predicate function into a single logical vector making it very useful in filter. So, the output should look like this: May 28, 2022 · 1. I would appreciate all the help there is! Thanks!!! Can the mutate be used when the mutation is conditional (depending on the values of certain column values)? This example helps showing what I mean. If the name doesn’t exist, it will create a new variable (column is appended at the end of existing columns). You can install it from CRAN with: install. We name the column we’re mutating and set the value. frame with several hundred columns, this isn't a great solution. This is actually the reason for the question. I realized (see comment above) that I was asking the wrong question, as what I really wanted is for the "count" column to not be included in the mutate_all() call (because I need the counts but 100 is the result of count/count *100. Jul 3, 2018 · Now I would like to create dummy variables for these columns for which proportion of 0's is greater than 0. Essentially, that’s all it does. Source: R/if-else. Compared to the base R equivalent, ifelse(), this function allows you to handle missing values in the condition with missing and always takes true, false, and missing into account when determining what the output type should be. data %>% mutate Add new column to dataframe in R Sep 14, 2020 · Couldn't quite find a solution to this one, looking for some guidance. The mutate function from dplyr package is used to create new columns or modify existing columns in a data frame, while retaining the original structure. How can I accomplish that with dplyr? Jun 26, 2021 · 1. I am thinking of a row-wise analog of the summarise_each or mutate_each function of dplyr. This function uses the following basic syntax: Method 1: Add Column at End of Data Frame. The best solution I know of is to use: dplyr::select(mtcars, -which(names(mtcars) %in% drop)) Here is some sample code and data showing I want to take the string after the final underscore character in the id column in order to create a new_id column. ) %>% as. Below is a minimal example of the data frame: The issue is about binary classification based on multiple criteria. Here is my solution: df <- iris Set a name key with the columns to be renamed and the new values: col_name = "colA" x %>% mutate(new_col = !!as. We could use each unquoted column name to remove them: dplyr::select(mtcars, -disp, -drat, -gear, -am) But, if you have a data. Jun 30, 2022 · 1. Method 2: Check if Partial Column Name Exists in Data Frame. If these requirements aren't met no donut will be awarded (coded 0). df <- data. Obviously I can use %>% mutate(X = D * E) %>% select (-D, -E), but for more elaborate situations, is there a way to do it in a single command? Like transmute(), but only discarding the columns that were mentioned. I came here because I had the same problem as number 4. rnorm(5) Basic usage. We have to use dplyr::cur_column() to get the column name within across (deparse(substitute()) just returns "col"). Great answers all around. It will just issue a warning for columns that don't exist. Warning message: Unknown columns: `clearness` From dplyr 1. May 27, 2018 · Mutate() new column based on a vector of character strings, of varying length, found in another column 1 Conditional mutating of the R data frame based on the strings case 1: keep original columns. frame column b: 10 + 20 + 10. This really isn't the type of transformation that dplyr is best able to make easier. If the name already exists, it will update the column. 11 true blue. Always easier to illustrate with Feb 9, 2022 · my_df <- data. A common task when working with data is renaming columns, which dplyr handles efficiently using the rename() function. if_any () and if_all () Oct 26, 2018 · Update dplyr 1. In fact, you can use/access that (each-group temporary-new) data inside that function using cur_group() (?cur_across). Mar 3, 2023 · I want to mutate columns that start with the letter "G", so G1_0_20, G2_20_40, etc. frame(A = rnorm(5) , B = rnorm(5) , C = rnorm(5)) colToAdd <- c("B" , "D") then apply the check if the column exists NULL produced else add your column e. [[1]] =". So this. If there are possibly more that one start_time per id, then you can use the same function but rowwise and with mutate: result <- df1 %>% rowwise () %>% mutate (count = length Mar 26, 2015 · How do i find the first occurence of a certain value, within a group using dplyr. name(col_name)) That works with a static variable. Dynamically determine if a dataframe column exists and mutate if it does. Group Group2 1 5678 1 2000-01-01 2010-05-02 A A 2 5678 2 2010-05-02 2010-05-02 A A 3 1234 1 2000-01-01 2015-06-03 B A&B 4 1234 2 2015-06-03 2015-06-03 A A&B It keeps one from having to write a line to hard code in each new column desired. Also, I am worried that group_by or mutate, or some other function might do implicit rearrangement of the rows, don't know if this could be an issue? Sep 25, 2020 · Error: Can't rename columns that don't exist. Any insight is appreciated. If columns that start with G (G1_0_20, G2_20_40,etc) has value of 1, then its value should match column "Score", otherwise NA. The syntax is identical to across, but these verbs were added to help fill this need: if_any/if_all. . newColumnName1 = "oldColumnName1", newColumnName2 = "oldColumnName2". Jun 27, 2017 · dplyr::mutate_if fails when column names contain spaces. " when the column does exist with dplyr. For example, for each column where the max is 5 and the column name contains "xy", apply a function. In both cases I used trimws to trim whitespace, also you don't need BP2018_spread$ as mutate understands column names. The id column entry always has 2 underscore characters and it's always the final substring I would like. kbzsl March 25, 2021, 6:53pm 1. The data entries in the columns are binary(0,1). Then, group by id and use this to summarise. Feb 2, 2015 · R dplyr method mutate variable if exists. Can I use dplyr::mutate to operate on different rows? 0. Add a new data frame column with mutate in a specific location. Add multiple data frame columns with mutate in R. This is useful for checking your work, as it displays inputs and outputs side-by-side. 23 false red. Jan 27, 2017 · R dplyr: mutate a column for specific row range. Based on the following logic. How to use mutate in R. vector)) This particular syntax applies the scale() function to each variable in the data frame that contains the string ‘starter’ in the column name. Use newly created variables inside the next variables within mutate in R. You might consider using for loops in this case, but trying to do that with mutate() probably isn't going to be pleasant. Mar 25, 2021 · Mutate only if a column exists in a dataframe - tidyverse - Posit Community. Dec 22, 2023 · P. So it is possible that if I can create a new variable--if and only if it does not yet exist--with values of "0" I can proceed. 2 and a. Apr 16, 2018 · I want to add a col var2 based on the value of var via dplyr mutate. When you group a tibble, all the functions applied after grouping use the grouped data, excluding the grouping variables (?group_by). In contrast to options a. I wasn't Oct 28, 2021 · This works nicely too . Romain Francois. These dummy variables would have value 0 if there is 0 in original column, and 1 if opposite. Feb 5, 2024 · Issue. The value can be: A vector of length 1, which will be recycled to the correct length. Method 3: Check if Several Exact Column Names All Exist in Data Frame. if_else() is a vectorized if-else. We’re happy to announce the release of dplyr 1. In fact, using any of the dplyr functions is very straightforward, because they are quite well designed. vars argument lets you specify columns in the same way that you would specify columns in select(), provided you put that specification inside the function vars(). frame(a = c(1,2,3), b = c(4,5,6)) my_df %>% dplyr::rename(aa = a, bb = b, cc = c) Error: Can't rename columns that don't exist. , year = b)) Steps: for the first row mutate, it filters the whole data. Jan 17, 2023 · You can use the mutate () function from the dplyr package to add one or more columns to a data frame in R. In addition, the best tidy_select helper for this case is any_of as it will perform on the variables which exist, but ignores those that don't exist (without warning message). Mar 28, 2021 · I followed the dplyr-solution here: converting multiple columns from character to numeric format in r to convert multiple character columns to numeric. Ideally, i would use dplyr::mutates function (mutate, mutate_at), because I need a solution that also Naming. Sep 6, 2022 · You can use the following basic syntax in dplyr to mutate a variable if a column contains a particular string: library (dplyr) df %>% mutate_at(vars(contains(' starter ')), ~ (scale(. Jun 16, 2020 · EDIT June 17th: I just checked what happens after "spread", and indeed there is no "negative" variable/column. For example, a way to simplify the mutate function in the following code: df &lt;- Aug 7, 2023 · Let’s discuss how to remove the column that contains the character or string. x / 2. For example, if the variable names contains "demo" calculate the mean, and if the name contains "meas" calculate the Oct 31, 2020 · I have a grouped data. In other words Is there a way to add columns of NA in the tidyverse when a column does not exist? My current attempt works for adding new variables where the column doesn't exist (top_speed) but fails when the column already exists (mpg) - it sets all observations to the first value Mazda RX4. 0, any_of() could be used: warning if the column name does not exist, in this case 'bad_column': Similar questions have been certainly asked but my one is much easier and unfortunately I really could not dissect the answer from them so here is my specific, probably simple case: df &lt;- data. , loop across any_of the columns in 'nms' i. x Column `c` doesn't exist. Easier option is any_of - create two formal arguments - one for inputting the dataset and second for the column names to convert to uppercase as string (nms). First, define a list with your column names you want to rename in a data frame df. 3. Jan 10, 2015 · 1 through 3 are answered above. Whereas I want to mutate based on a corresponding value in a column outside dplyr is a popular R package for data manipulation, making it easier for users to work with data frames. funs = list(~ . Sep 25, 2020 · Error: Can't rename columns that don't exist. R - dplyr - How to mutate rows or divitions between rows. Add a new data frame column and drop used columns with mutate in R. tidyverse. Fortunately this is easy to do using the mutate() and case_when() functions from the dplyr package. Now I use dplyr::mutate_if to set those columns to 0, whose names are contained in the character vector. frame( xx1 = c(0, 1, 2) Jul 23, 2021 · EDIT df also contains other columns with other irrelevant data! I have a vector with correct answers to each of qa1-3 and qb1-3 in sequence with the columns. I have the following situation: I have a tibble and a character vector that conatins some of said tibbles column names. correct_answer <- c(1,3,2,2,1,4) (i. "unused" retains only the columns not used in to create new columns The name gives the name of the column in the output. Sep 8, 2021 · By default, mutate seems to only work with columns that already exist, but my df comes different each time. The columns I would like to create will contain only "0" for example. Jul 20, 2018 · I want to produce a data frame with columns A, B, C, X, where X = D * E. frame by values equal or less than 2022, then summarize it by making the sum of the filtered data. NULL, to remove the column. For this, we need to specify a logical condition within the mutate command: data %>% # Apply mutate. Related. If M2 is more than UCL, MM2 will be "UP" and otherwise "NULL". I can't quite figure out how to use mutate across with ifelse statement. Aug 16, 2022 · A solution using dplyr::mutate() Suppose that your data frame is diamonds. 4th new column depends only on the 4th existing columns. Otherwise, do not change PREF. cols, selects the columns you want to operate on. It is probably very easy but I can't find a solution. The code is_all_numeric &lt;- function(x) { Jan 20, 2021 · Assuming you don't want to overwrite the column if it is already present in your data you can use add_column along with an if condition to check if the column is already present. But I have several M column (like M1~M1005) so that I would like to make some code such as mutate_each dplyr is a popular R package for data manipulation, making it easier for users to work with data frames. Mar 31, 2017 · I want to mutate using column indexes for both the source and the destination of the mutate: gives: Error: unexpected '=' in "iris %>% head %>% mutate(. if . vars = vars(B:E), . Given this sample data: I want to use new column E to categorize A by whether B == 1, C == 2, and D > 0. if test == "false", I would like to mutate PREF = "orange". Mar 5, 2015 · My question involves summing up values across multiple columns of a data frame and creating a new column corresponding to this summation using dplyr. I am trying to use dplyr to mutate (or mutate_if?) column2 of a dataframe based on the contents of column1. d %>% rename(x = "a", y = "a") renames the same a column twice, first with x and then with y. data. However, I have been unable to change the variable to represent the column. funs=funs mess, but that was not the point of the question. This can also be a purrr style formula (or list of formulas) like ~ . How do I take a column name based on contents of a different column? This question is basically the opposite of this: dplyr - mutate: use dynamic variable names. 1, a. df animals isanimal 1 cat animal 2 cat animal 3 dog NA 4 dog NA 5 mouse animal Jul 26, 2017 · I would like to make new columns with this condition: If M1 is more than UCL, MM1 will be "UP" and otherwise "NULL". Syntax. if there is only one unnamed function (i. "all" retains all columns from . 5. . Method 1: Using contains () contains () removes the column that contains the given substring. mutate() is used to both change the values of an existing column and make a new column. Jun 11, 2018 · select(Web_Bigram_Counts_By_Company, starts_with("word")) works great to select the columns whose names start with 'name', but when I use it in the call to mutate I get this error: Column 'stopword_count' must be length 360463 (the number of rows) or one, not 2 If you have a vector of names that you know should be in it, the following will check if they already have a column. An alternative is to break the pipe and rename. for the second row do the same and now filter the value of b equal or smaller than 2021 being the mutate output: 20 + 10 Oct 6, 2017 · I am trying to use mutate_if to perform calculations based on the variable name. fns, is a function or list of functions to apply to each column. columnNamesToRename <-. frame and leave out the ones that are not present from the vector, convert to Jul 10, 2021 · I can't figure this one out. Aug 23, 2018 · I want to mutate a column based on multiple conditions. This is the default. This was my first-ever answer on SO! I used SO extensively over the past year and taught myself R from absolute scratch, enough to build a commercial (prototype) DB app that does monthly reporting & analysis on a a very large group of disparate source files. Basically, I want to rotate coordinates of points (in columns x, y, z) in 3D space and store in a new columns (x_rot, y_rot, z_rot). 0. Silly, but I keep wishing for this bit of conciseness. It uses tidy selection (like select() ) so you can pick variables by position, name, and type. There is already standard ways to call the column with column names. ) ? The reason is that the ". list(. May 12, 2017 · If you're using dplyr version >= 1. Modifying the else condition to TRUE in this case does everything in one line. frame and want to mutate a column conditionally checking all() of the certain column. It enables users to apply functions or operations to data within a data frame and store the results as new variables. for qa1,qa2,qa3,qb1,qb2,qb3) Desired manipulation 1. ℹ Input `c` is `a/b`. frame with 3 columns; I am grouping by the column code and if the column B of that group is entirely of NA, I want to copy the values from column A and otherwise keep the original non NA values of B 3 days ago · Use mutate_all() from dplyr package to change values on all columns, the following example replaces all instances of Street with St on all columns. I'm trying to do this using dplyr and ifelse. The rename() function in dplyr is particularly useful when dealing with datasets that have columns with unclear or Apr 26, 2022 · Theoretically, mutate_if only extract column values, not column names, so ~ names(. Sure, you stripped out all the . It is also worth noting that there must be at least half as many rows as there are columns for this approach to work. 0, the scoped variants of mutate such as _at or _all were replaced by across(). Here is a base solution, using traditional subsetting, to this, which returns columns "ab" and "ad": df[, df[2,] == "b"] Is there a way to accomplish this using dplyr? Aug 8, 2018 · The mutate() function is a function for creating new variables. Getting "Can't subset columns that don't exist. This time, Mutate column if column exists loop dplyr. Here is a sample of a data set I have : ID Rank Date Date2. If var == 'b1' or var == 'b2' then All B If var == 'c1' or var == 'c2' then All C else var. Nov 22, 2017 · I am trying to find a better way to run a mutate() on a combination of columns based on parts of the column names. frame-like object that already has names. R - own function in mutate_if from dplyr. In case you want to specifically check for one column, a non-conventional way to do that would be to use exists. mutate ( x4 = ( x1 == 1 | x2 == "b")) # x1 x2 x3 x4 # 1 1 a 3 TRUE # 2 2 b 3 TRUE # 3 3 c 3 FALSE # 4 4 d 3 FALSE # 5 5 e 3 FALSE. 4 false yellow. Like all of the dplyr functions, it is designed to do one thing. When I execute the code below, the entire column changes to NA. 1. diamond here). ID TEST PREF. Since we have Street on the address and work_address columns, these two would get updated. May 4, 2017 · R dplyr drop column that may or may not exist select(-name) 1. I would like to create new empty columns with dplyr, based on a vector containing the new variables names. dplyr. If M3 is more than UCL, MM3 will be "UP" and otherwise "NULL". The variants of mutate, such as mutate_all, mutate_at, mutate_if, and mutate_across, allow you to apply functions to all selected or conditional variables or variables that match a pattern. packages ("dplyr") You can see a full list of changes in the release notes. funs argument accepts an anonymous function defined on the fly inside a call to list(). Using mutate() is very straightforward. Jul 9, 2021 · Execute dplyr operation only if column exists. Nov 2, 2018 · Is there a single-call way to assign several specific columns to a value using dplyr, based on a condition from a column outside that group of columns? My issue is that mutate_if checks for conditions on the specific columns themselves, and mutate_at seems to limit all references to just those same specific columns. The names of the new columns are derived from the names of the input variables and the names of the functions. I want to tell dplyr to try the mutation, else if something goes wrong just make new feature c all NA_real_ as opposed to a / b. Dec 15, 2015 · 3. A vector the same length as the current group (or the whole data frame if ungrouped). The second argument, . Syntax: select (dataframe,-contains (‘sub_string’)) Here, dataframe is the input dataframe and sub_string is the string present in the column name will be removed. A dataframe: a = 1:3, b = c(2,2,2) Sometimes b is present, in which case one can do this: But, sometimes feature b will not be present, in which case: Error: Problem with `mutate()` input `c`. I'm trying to clean this up. Removing a column from a dataframe based on a conditional. You can use this dummy data df and colToAdd columns to check if not exists to add. My goal is to write a pipeable function which applies a (custom) function to a specified column; when the column is missing the original dataframe is returned (without any error/warning). ) Next, remove the elements of the list, which have a column name as their name, but is not a column name of your data frame: columnNamesToRename Mar 28, 2017 · I'd like to use dplyr functions to group_by and conditionally mutate a df. The following code gives the desired result, but it I'm wondering if there is a shorter way to do it. In dplyr 1. mutate(new_col=c(1, 3, 3, 5, 4)) Method 2: Add Column Before Specific Column. Sep 6, 2020 · and welcome here. If the name was in the list of columns to mutate, I used the same case_when as above, and output a tibble with two columns: one is the original column, with its name assigned using quo_name and the := operator, and the other is the new values column, with the same name but _n appended. Apr 10, 2018 · I think this answer is just as clumsy as the examples in the question. The first argument, . The syntax of the mutate function is the following: Syntax. ze wd zp ht pt dx av ad yj kx