3) Example 1: Compute Mean by Group Using aggregate Function. The table of content looks like this: 1) Definition & Basic R Syntax of aggregate Function. 2) Creation of Example Data. … If each call to FUN returns a vector of length n, and simplify is TRUE, then apply returns an array of dimension c(n, dim(X)[MARGIN]) if n > 1. The function has the following syntax: The function has the following syntax: sapply(X, # Vector, list or … across.Rd. Below are the most common forms of apply functions. apply (data_frame, 1, function, arguments_to_function_if_any) The second argument 1 represents rows, if it is 2 then the … And, there are … apply() function takes 3 arguments: data matrix; row/column operation, – 1 for row wise operation, 2 for column wise operation; function to be applied on the data. For that, you have two related functions from the apply family at your disposal sapply () and lapply (). apply() function is the base function. If n equals 1, apply returns a vector if MARGIN has length 1 … Apply a function (or a set of functions) to a set of columns Source: R/across.R. apply(data, 1, function(x) {ifelse(any(x == 0), NA, length(unique(x)))}) #  1 NA 2 Basically ifelse returns a vector of length n if its first argument is of length n. You want one value per row, but are passing more … You can do this in several ways, depending on the value you specify to the MARGIN … The sapply function in R applies a function to a vector or list and returns a vector, a matrix or an array. The apply () function works on anything that has dimensions in R, but what if you don’t have dimensions? Apply functions are a family of functions in base R, which allow us to perform actions on many chunks of data. We begin by first creating a straightforward list > x=list(1,2,3,4) we use the rapply … when 1 is passed as second parameter, the function … Apply family in R. The apply family consists of vectorized functions. across() makes it easy to apply the same transformation to multiple columns, allowing you to use select() … apply () function in R The apply command in R allows you to apply a function across an array, matrix or data frame. We will learn how to apply family functions by trying out the code. R has a more efficient and quick approach to perform iterations – The apply family. To call a function for each row in an R data frame, we shall use R apply function. … rapply stands for recursive apply, and as the name suggests it is used to apply a function to all elements of a list recursively. An apply function is a loop, but it runs faster than loops and often with less code. In this tutorial you’ll learn how to apply the aggregate function in the R programming language.