R Error object not found r

The “object not found r” error message is a fairly basic one it shows up on the console when you are running R code. It is not a difficult problem to find and fix but depending upon the situation and the cause it may take time. However, once you find the source of the difficulty finding the solution is fairly easy particularly once you have gained some experience with the base R programming language.

The error’s circumstances.

The “object not found r” error message does not necessarily involve a function, because it can occur anytime you call an r object. It occurs when R can not find a variable in a data set. As a result, it an easy error message in R script to understand.

# R error object not found
> a
Error: object 'a' not found

Here is an example of the simplest possible case of this message. In this case, an object labeled “a” is called without having been previously defined. This caused the triggering of our error message. It occurs anytime you call an object without defining it first.

What is causing this problem?

Technically is this error message has only one real cause and that is the inability of the system to find a specified object that is called. However, the immediate cause can be one of several different things in your R session document.

1. Misspelling object names.

# object not found r misspelled object names
> name = c("Bob", "Tom", "Sue")
> Nome

2. Neglecting to define the variable that you are calling.

> a

3. Calling a variable that is part of another specified object such as a data frame.

# variable part of data frame object not found
>q = data.frame("x" = c(5, 2, 7 ), "y" = c(3, 9, 1))
>x

4. Calling a variable before you define it.

# object not found r calling undefined variable
>state
>state = c("SC", "CT", "NJ")

Each of these examples triggers our message in a different manner but ultimately the cause is the same, and that is calling an undefined object. It is particularly easy to make such mistakes when the data you are working with are not native to your R script but instead, you import each value from a package or other file external to your R code.

How to fix this problem.

Fixing the four examples from the last section it’s quite simple once you identify the problem.

1. Misspelling object names.

> name = c("Bob", "Tom", "Sue")
> name

2. Neglecting to define the variable that you are calling.

> a = 5
> a

3. Calling a variable that is part of another object such as a data frame.

> q = data.frame("x" = c(5, 2, 7 ), "y" = c(3, 9, 1))
> q$x

4. Calling an item before you define it.

> state = c("SC", "CT", "NJ")
> state

These cases have straightforward solutions where you are simply fixing the problem once they are founded. It is also possible to do an in code check of the object’s existence with the exists() function argument.

> exists("name")
[1] FALSE

> name = c("Bob", "Tom", "Sue")
> exists("name")
[1] TRUE

In the first case, the exists() function gave a response of FALSE because “name” had not been created yet. In the second case, “name” had already been defined and so the function gave a response of TRUE. This allows you to use an IF statement to skip over the calling routine if the item had not been defined yet.

Regardless of the nature of the app, you need to avoid this problem. You can do it by making sure your code is exactly right or you can provide an internal check of an item’s existence to ensure did you do not call a non-existent item. These solutions can also help fix working directory errors in an R markdown document as part of the base R programming language.

R Error object not found r