# Getting and Setting Length of the Vectors in R Programming – length() Function: Title change need

In R, the length of a vector is the number of elements it contains. Vectors can be of different types, such as numeric, character, or logical, and the `length()` function is a versatile way to determine the number of elements in a vector.

length() function in R Programming Language is used to get or set the length of a vector (list) or other objects.

## Getting the length of an object in R Programming

Here we are going to get the length of the vector in R Programming, for this, we will use the length() function.

Syntax: length(x)

Parameters:

• x: vector or object

## R

 `# R program to illustrate``# length function` `# Specifying some vectors``x <- ``c``(6)``y <- ``c``(1, 2, 3, 4, 5)` `# Calling length() function``# to get length of the vectors``length``(x)``length``(y)`

Output :

`[1] 1[1] 5`

## R

 `A = ``matrix``(``     ` `  ``# Taking sequence of elements ``  ``c``(1, 2, 3, 4, 5, 6, 7, 8, 9),``   ` `  ``# No of rows``  ``nrow = 3,  ``   ` `  ``# No of columns``  ``ncol = 3,        ``   ` `  ``# By default matrices are in column-wise order``  ``# So this parameter decides how to arrange the matrix``  ``byrow = ``TRUE`        `)``print``(A)` `# length of A``length``(A)`

Output:

`     [,1] [,2] [,3][1,]    1    2    3[2,]    4    5    6[3,]    7    8    99`

### Example 3: Getting the length of the Dataframe

Here BOD is dataframe has 6 rows and 2 columns giving the biochemical oxygen demand versus time in an evaluation of water quality. and we are going to get the length of this dataframe.

## R

 `print``(BOD)` `length``(BOD)`

Output:

`  Time demand1    1    8.32    2   10.33    3   19.04    4   16.05    5   15.66    7   19.82`

Note: If the parameter is a matrix or dataframe, it returns the number of variables:

## R

 `# R program to create a List and get the len` `# The first attributes is a numeric vector``# containing the employee IDs which is created``# using the command here``empId = ``c``(1, 2, 3, 4)` `# The second attribute is the employee name``# which is created using this line of code here``# which is the character vector``empName = ``c``(``"Debi"``, ``"Sandeep"``, ``"Subham"``, ``"Shiba"``)` `# The third attribute is the number of employees``# which is a single numeric variable.``numberOfEmp = 4` `# We can combine all these three different``# data types into a list``# containing the details of employees``# which can be done using a list command``empList = ``list``(empId, empName, numberOfEmp)` `print``(empList)` `print``(``"Length of the list:"``)``length``(empList)`

Output:

`[[1]][1] 1 2 3 4[[2]][1] "Debi"    "Sandeep" "Subham"  "Shiba"  [[3]][1] 4[1] "Length of the list:"3`

### Example 5: Getting the length of the string

In R Language, we can not easily get the length of the string, first, we have to get the character of the string using split and then unlist each character to count the length.

## R

 `# R program to split a string` `# Given String``string <- ``"Geeks For Geeks"` `# Basic application of length()``length``(string)   ` `# unlist the string and then count the length``length``(``unlist``(``strsplit``(string, ``""``)))`

Output:

`115`

## Setting length of the object in R Programming

Here we are going to set the length of the vector in R Programming, for this we will use length() function.

Syntax: length(x) <- value

Parameters:

• x: vector or object

## R

 `# R program to illustrate``# length function` `# Specifying some vectors``x <- ``c``(3)``y <- ``c``(1, 2, 3, 4, 5)``z <- ``c``(1, 2, 3, 4, 5)` `# Setting length of the vector``length``(x) <- 2``length``(y) <- 7``length``(z) <- 3` `# Getting elements of the ``# new vectors``x``y``z`

Output:

`[1]  3 NA[1]  1  2  3  4  5 NA NA[1] 1 2 3`

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