How to Fix in R: Argument is not numeric or logical: returning na

In this article, we are going to see how to fix in R argument is not numeric or logical returning na.

This is the warning message that you may face in R. It takes the following form:

Warning message:

In mean.default(dataframe) : argument is not numeric or logical: returning NA

The R compiler produces such type of error when we try to compute the mean of an object in R but the object contains non-numerical or illogical values. This article focuses on how we can fix this error.

When this error might occur

Let’s create a data frame first:

R

# Create a data frame
dataframe <- data.frame(students=c('Bhuwanesh', 'Anil',
                                   'Suraj', 'Piyush',
                                   'Dheeraj'),
                 section=c('A', 'A', 'C', 'C', 'B'),
                 minor=c(87, 98, 71, 89, 82),
                 major=c(80, 88, 84, 74, 70))

# Print the dataframe
print(dataframe)

Output:

Output

Now we will try to compute the mean of the values in the section column.

Example:

R

# Create a data frame
dataframe <- data.frame(students=c('Bhuwanesh',
                                   'Anil', 'Suraj',
                                   'Piyush', 'Dheeraj'),
                 section=c('A', 'A', 'C', 'C', 'B'),
                 minor=c(87, 98, 71, 89, 82),
                 major=c(80, 88, 84, 74, 70))

# Try to calculate mean of values in
# section column
mean(dataframe$team)

Output:

Output

As you can see in the output, the R compiler produces “argument is not numeric or logical: returning NA” as the section has non-numeric values.

Let’s compute the mean of the data frame now:

Example:

R

# Create a data frame
dataframe <- data.frame(students=c('Bhuwanesh',
                                   'Anil', 'Suraj',
                                   'Piyush', 'Dheeraj'),
                 section=c('A', 'A', 'C', 'C', 'B'),
                 minor=c(87, 98, 71, 89, 82),
                 major=c(80, 88, 84, 74, 70))

# Try to calculate mean of values
# of the dataframe
mean(dataframe)

Output:

Output

How to avoid this warning ?

The only way to avoid this warning is to use the mean() function with vectors having numeric values only. For example, In the above example we can calculate the mean of the minor column as it contains numerical values only:

R

# Create a data frame
dataframe <- data.frame(students=c('Bhuwanesh', 'Anil',
                                   'Suraj', 'Piyush',
                                   'Dheeraj'),
                 section=c('A', 'A', 'C', 'C', 'B'),
                 minor=c(87, 98, 71, 89, 82),
                 major=c(80, 88, 84, 74, 70))

# Try to calculate mean of values stored
# at the column minor in the dataframe
mean(dataframe$minor)

Output:

Output

Mean using sapply() function

R provides the sapply() function to compute the mean of values in every column of the data frame.

R

# Create a data frame
dataframe <- data.frame(students=c('Bhuwanesh', 'Anil',
                                   'Suraj', 'Piyush',
                                   'Dheeraj'),
                 section=c('A', 'A', 'C', 'C', 'B'),
                 minor=c(87, 98, 71, 89, 82),
                 major=c(80, 88, 84, 74, 70))

# Try to calculate mean of values stored
# at the column minor in the dataframe
sapply(df, mean, 2)

Output:

Output

As you can see in the output, the R compiler produces the warning message but also calculate the mean values of the columns having numeric values in it. We can avoid the warning completely by explicitly specifying the columns having numeric values.

R

# Create a data frame
dataframe <- data.frame(students=c('Bhuwanesh', 'Anil',
                                   'Suraj', 'Piyush',
                                   'Dheeraj'),
                 section=c('A', 'A', 'C', 'C', 'B'),
                 minor=c(87, 98, 71, 89, 82),
                 major=c(80, 88, 84, 74, 70))

# Try to calculate mean of values stored
# at the column minor in the dataframe
sapply(dataframe[c('minor', 'major')], mean, 2)

Output:

Output

This time the program compiled successfully without any warning message.