How to Fix in R: incorrect number of dimensions

In this article, we will discuss how we can fix the “incorrect number of dimensions” error in R Programming Language.

One common error that one may face in R is:

Error in [x, 10] : incorrect number of dimensions

The R compiler produces such an error when one tries to refer to an object by providing more dimensions than the actual dimension the object has. 

Reproducing the error:

Let us consider an example in which we have a vector initialized with 5 values in it.

R

# Initialize a vector
myVector <- c(10,13,2,6,12)

As you can see in the snippet that myVector is a one-dimensional vector having 5 values in it. Now suppose we mistakenly try to subset it with two dimensions:

Example:

In this program, we are accessing the value stored at the 4th row and the 1st column. 

R

# Initialize a vector
myVector <- c(10, 13, 2, 6, 12)

# Access the value stored at 4th row
# and 1st column
myVector[4, ]

Output:

Output

Example:

In this program, we are accessing the value stored at the 1st row and the 4th column. And here the R compiler produces this error because we are trying to subset with 2-dimensions while the vector has 1-dimension.

R

# Initialize a vector
myVector <- c(10, 13, 2, 6, 12)

# Access the value stored at 4th
# row and 1st column
myVector[, 4]

Output:

Output

How to fix this error:

We can fix this error easily by subsetting with one dimension.

Example:

Consider a program in which we are accessing the fifth value of the vector (Treating as 1-dimension data structure).

R

# Initialize a vector
myVector <- c(10, 13, 2, 6, 12)

# Access the value stored at 5th position
myVector[5]

Output:

Output

Note: A large number of contiguous values of the vector can also be accessed with subset by one dimension:

Example:

In this program, we are accessing elements using one-dimension subset values from position equal to 2 to the position equal to 5 (inclusive). 

R

# Initialize a vector
myVector <- c(10, 13, 2, 6, 12)

# Access the value stored at 5th position
myVector[2:5]

Output:

Output