# Calculate the Mean of each Column of a Matrix or Array in R Programming – colMeans() Function

`colMeans()` function in R Language is used to compute the mean of each column of a matrix or array.

Syntax: colMeans(x, dims = 1)

Parameters:
x: array of two or more dimensions, containing numeric, complex, integer or logical values, or a numeric data frame
dims: integer value, which dimensions are regarded as ‘columns’ to sum over. It is over dimensions 1:dims.

Example 1:

 `# R program to illustrate ` `# colMeans function ` ` `  `# Initializing a matrix with ` `# 3 rows and 3 columns ` `x <``-` `matrix(rep(``1``:``9``), ``3``, ``3``) ` ` `  `# Getting matrix representation ` `x ` ` `  `# Calling the colMeans() function ` `colMeans(x) `

Output:

```     [, 1] [, 2] [, 3]
[1, ]    1    4    7
[2, ]    2    5    8
[3, ]    3    6    9

 2 5 8
```

Example 2:

 `# R program to illustrate ` `# colMeans function ` ` `  `# Initializing a 3D array ` `x <``-` `array(``1``:``12``, c(``2``, ``3``, ``3``)) ` ` `  `# Getting the array representation ` `x ` ` `  `# Calling the colMeans() function ` ` `  `# for dims = 1, x[, 1, 1], x[, 2, 1], x[, 3, 1], ` `# x[, 1, 2] ... are columns ` `colMeans(x, dims ``=` `1``) ` ` `  `# for dims = 2, x[,,1], x[,,2], x[,,3] ` `# are columns ` `colMeans(x, dims ``=` `2``) `

Output:

```,, 1

[, 1] [, 2] [, 3]
[1, ]    1    3    5
[2, ]    2    4    6,, 2

[, 1] [, 2] [, 3]
[1, ]    7    9   11
[2, ]    8   10   12,, 3

[, 1] [, 2] [, 3]
[1, ]    1    3    5
[2, ]    2    4    6

[, 1] [, 2] [, 3]
[1, ]  1.5  7.5  1.5
[2, ]  3.5  9.5  3.5
[3, ]  5.5 11.5  5.5

 3.5 9.5 3.5
```
My Personal Notes arrow_drop_up Check out this Author's contributed articles.

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.

Article Tags :

Be the First to upvote.

Please write to us at contribute@geeksforgeeks.org to report any issue with the above content.