R Error : ‘names’ attribute must be the same length as the vector

This article shows how to deal with the “Error in names() : ‘names’ attribute must be the same length as the vector” in the R programming language.

The tutorial will contain the following:

Let’s take a look at some R codes in action!

Example Data

We use the following data as basement for this R programming tutorial:

my_vector <- 1:3                                 # Create example vector
my_vector                                        # Print example vector
# [1] 1 2 3

Have a look at the previous output of the RStudio console. It illustrates a vector object with three vector elements.

Next, we have to create a vector with potential names for our vector object:

my_names <- letters[1:4]                         # Create vector of names
my_names                                         # Print vector of names
# [1] "a" "b" "c" "d"

Our names vector contains four potential names. Let’s assume that we want to assign these names to our vector object.

Example 1: Reproduce the Error in names() : ‘names’ attribute must be the same length as the vector

Example 1 shows how to replicate the error message in “names() : ‘names’ attribute must be the same length as the vector”.

We might try to assign our names to the vector object using the names() function as shown below:

names(my_vector) <- my_names                     # Try to assign names
# Error in names(my_vector) <- my_names : 
#   'names' attribute [4] must be the same length as the vector [3]

Unfortunately, the RStudio console returns the error message “‘names’ attribute must be the same length as the vector”.

The reason for this is that our vector of names is longer than our vector containing the values, i.e. my_vector has a length of three and my_names has a length of four.

Next, I’ll explain how to solve this problem.

Example 2: Fix the Error in names() : ‘names’ attribute must be the same length as the vector

The following R programming syntax explains how to get rid of the “Error in names() : ‘names’ attribute must be the same length as the vector”.

For this, we have to harmonize the number of elements in our vector of values and in our vector of names:

my_names_new <- my_names[1:length(my_vector)]    # Harmonize length of vector and names

The previous R code has created a new vector of names with a shorter length.

Now, we can assign this new vector of names to our vector of values:

names(my_vector) <- my_names_new                 # Properly assign names

No error appears. Let’s have a look at the updated version of our vector:

my_vector                                        # Print updated vector
# a b c 
# 1 2 3

As you can see, we have created a named vector object. Looks good!

In case you are facing the problems described in this tutorial, please make sure that you double-check why the number of vector elements was different compared to the number of names.

Is there a logical explanation or have there been any mistakes in the forefront?

Video & Further Resources

Do you need more info on the R programming codes of this article? Then you may want to have a look at the following video of my YouTube channel. In the video, I show the R code of this tutorial:

Also, you may want to read the related tutorials of my homepage.

• Handling Warning & Error Messages in R (List with Examples)
• Introduction to R Programming

To summarize: In this R tutorial you have learned how to avoid the “Error in names() : ‘names’ attribute must be the same length as the vector”. In case you have any additional questions, don’t hesitate to let me know in the comments.