Applying a Function over an Object in R Programming – sapply() Function

** sapply()** function in R Language takes list, vector or data frame as input and gives output in vector or matrix. It is useful for operations on list objects and returns a list object of same length of original set.

Syntax:sapply(X, FUN)

Parameters:X:A vector or an objectFUN:Function applied to each element of x

**Example 1:**

`# R program to illustrate` `# sapply function` ` ` `# Getting the value of Biochemical oxygen` `# demand data set` `BOD` ` ` `# Calling sapply() function which` `# will sum the data of each columns` `# of BOD` `sapply(BOD, ` `sum` `)` |

**Output:**

Time demand 1 1 8.3 2 2 10.3 3 3 19.0 4 4 16.0 5 5 15.6 6 7 19.8 Time demand 22 89

**Example 2:**

`# R program to illustrate` `# sapply function` ` ` `# Initializing a list` `mylist <` `-` `list` `(c(` `1` `, ` `2` `, ` `3` `, ` `4` `), c(` `2` `, ` `4` `, ` `6` `, ` `8` `), c(` `1` `, ` `3` `, ` `5` `, ` `7` `))` ` ` `# Calling the sapply() function which` `# will calculate mean of each vector elements` `sapply(mylist, mean)` |

**Output:**

[1] 2.5 5.0 4.0