Named Vectors in R

 

Named Vectors in R

A named vector is a vector in which each element is assigned a name. The names act as labels for the elements, making the vector easier to understand and allowing values to be accessed by name instead of only by position.

Syntax

vector_name <- c(Name1 = value1,
                 Name2 = value2,
                 Name3 = value3)

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Example 1: Creating a Named Vector

marks <- c(English = 85,
           Maths = 92,
           Science = 88)

print(marks)

Output

English   Maths     Science
   85      92        88

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Accessing Elements

By Name

marks["Maths"]

Output

Maths
   92

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By Position

marks[2]

Output

Maths
   92

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Displaying Names

Use the names() function to retrieve the names of the vector elements.

names(marks)

Output

[1] "English" "Maths" "Science"

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Modifying an Element

marks["Science"] <- 95

print(marks)

Output

English   Maths Science
      85      92      95

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Example 2: Returning Multiple Values from a Function

Named vectors are commonly used to return multiple values from a function.

statistics <- function(v)
{
    return(c(
        Sum = sum(v),
        Average = mean(v),
        Maximum = max(v),
        Minimum = min(v)
    ))
}

v <- c(10, 20, 30, 40)

result <- statistics(v)

print(result)

Output

     Sum  Average Maximum Minimum
100.0     25.0    40.0    10.0

Accessing individual values:

result["Sum"]

result["Average"]

result["Maximum"]

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Advantages of Named Vectors

• Makes the output more readable by assigning meaningful labels.
• Allows elements to be accessed using names instead of numeric indices.
• Reduces programming errors caused by incorrect indexing.
• Useful for returning multiple related values from a function.
• Simplifies the interpretation of statistical and computational results.

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Limitations

• All elements of a vector must have the same data type.
• A named vector cannot store mixed data types (e.g., numeric values and character strings together). In such cases, a list should be used.

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Applications of Named Vectors

• Returning multiple numerical results from a function.
• Storing subject-wise marks of a student.
• Representing monthly sales figures.
• Storing statistical measures such as mean, median, and standard deviation.
• Holding configuration parameters with descriptive names.

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Summary

A named vector is a vector whose elements are associated with descriptive names. It improves the readability of programs, enables easy access to elements using names, and is particularly useful when returning multiple values of the same data type from a function. For mixed data types, however, a list is the preferred data structure.