Convert Matrix to List of Column-Vectors in R (2 Examples)

In this R article you’ll learn how to divide a matrix into a list of column-vectors.

The article will contain the following:

Let’s dig in.

Introducing Example Data

We’ll use the data below as basement for this R programming tutorial:

data <- matrix(1:15, ncol = 3)# Create example matrix
data                                       # Print example matrix

Have a look at the previous table. It shows that our example matrix has five data points and three columns.

Example 1: Split Matrix into List of Column-Vectors Using split(), rep(), ncol() & nrow()

This example illustrates how to use the split, rep, ncol, and nrow functions to convert the columns of a matrix into a list of vectors.

Have a look at the following R code:

my_list1 <- split(data,                    # Split matrix into list
                  rep(1:ncol(data),
                      each = nrow(data)))
my_list1                                   # Print list of column-vectors
# $`1`
# [1] 1 2 3 4 5
# 
# $`2`
# [1]  6  7  8  9 10
# 
# $`3`
# [1] 11 12 13 14 15
#

As you can see in the RStudio console, we have created a list object containing three list elements. Each of these list elements contains the values of one of the matrix columns.

Example 2: Split Matrix into List of Column-Vectors Using lapply(), seq_len(), ncol() & function()

In Example 2, I’ll show an alternative to the R code of Example 1 that is based on the lapply, seq_len, ncol, and function commands.

Consider the following R programming syntax:

my_list2 <- lapply(seq_len(ncol(data)),    # Split matrix into list
                   function(x) data[ , x])
my_list2                                   # Print list of column-vectors
# [[1]]
# [1] 1 2 3 4 5
# 
# [[2]]
# [1]  6  7  8  9 10
# 
# [[3]]
# [1] 11 12 13 14 15
#

Te list that we have created in this example is the same as in Example 1. Which code you want to use is a matter of taste.

Video & Further Resources

Have a look at the following video of my YouTube channel. I’m explaining the examples of this article in the video.

In addition, you could have a look at the other tutorials on https://www.statisticsglobe.com/.

• Convert Row Names into Column of Data Frame
• Convert Matrix to Vector in R
• Split Data Frame into List of Data Frames Based On ID Column
• Convert List of Vectors to Data Frame
• All R Programming Examples

You have learned in this article how to split the variables of a matrix into a list of vectors in the R programming language. Let me know in the comments below, if you have additional questions.