How To Convert Numeric To Integer In R

The fundamental data types in R programming are numbers and integers. Integer data types represent entire integers without a fractional component, whereas numeric data types represent actual numbers. While having similar characteristics, these data types have unique characteristics and functions.

In some circumstances, changing numeric data types to integer data types can minimise memory use, speed up computations, guarantee data integrity, and boost programming productivity.

Discover the optimal strategy and efficiency for converting numeric data types to integer data types in R, as well as practical application cases when this conversion is required.

Why Convert Numeric to Integer in R?

Here are a few reasons why numeric to integer conversion is required:

  • Memory optimization: In R, integer data types occupy less memory than numeric data types.
  • Speed optimization: Due to the manner that floating-point arithmetic operations are implemented on the CPU, integer calculations in R are significantly quicker than these procedures.
  • Data integrity: Integer values can be used in situations where numeric numbers are inappropriate.
  • Ease of programming: For integer operations including bit manipulation, integer division, and modulus computations, R has specialised functions for integer arithmetic.
  • Compatibility with other systems: Other systems or applications may occasionally demand that data be in integer format.

Various Approaches to convert numeric to Integer in R:

  • Truncation method
  • Rounding method
  • Flooring method
  • Conversion method
  • Conversion method

1. Truncation method:

Using this technique, a numeric number is transformed into an integer by removing the decimal component.

Code:-

# Generate a random numeric value
x <- 3.7

# Apply the truncation method
y <- trunc(x)

# Print output
cat("Original value:", x, "\n")
cat("Truncated value:", y, "\n")

Output:-

Original value: 3.7
Truncated value: 3

Explanation:

  • To convert a numeric number to an integer value in R, use the trunc() function.
  • For instance, the number 3 will be returned by trunc(3.7).
  • A random numeric value of 3.7 is assigned to the variable x.
  • The trunc() function is applied on x to truncate the decimal component of the value and returns an integer.
  • The truncated value is stored in a new variable y.
  • The cat() function is used to print the original and truncated values in the console.

2. Rounding method:

The closest integer number is used in this approach to round a numeric value.

Code:-

# Generate a random numeric value
x <- 3.7

# Apply the rounding method
y <- round(x)

# Print output
cat("Original value:", x, "\n")
cat("Rounded value:", y, "\n")

Output:-

Original value: 3.7
Rounded value: 4

Explanation:

  • To round a numerical number to the closest integer, use R’s round() function.
  • For instance, round(3.7) will produce the integer 4
  • The round() function is used to round the x value, which is 3.7, to the nearest integer, which is 4.

3. Flooring method:

With this technique, a numerical number is rounded to the nearest integer.

Code:-

# Generate a random numeric value
x <- 3.7

# Apply flooring method
y <- floor(x)

# Print output
cat("Original value:", x, "\n")
cat("Floored value:", y, "\n")

Output:-

Original value: 3.7 
Floored value: 3 

Explanation:

  • To round a numerical number to the closest integer, use R’s floor() function.
  • For instance, the number 3 will be returned by floor(3.7).
  • The floor() function is used to round down the x value, which is 3.7, to the nearest integer, which is 3.

4. Ceiling method:

The closest integer value is used in this procedure to round a numeric number.

Code:-

# Generate a random numeric value
x <- 3.7

# Apply ceiling method
y <- ceiling(x)

# Print output
cat("Original value:", x, "\n")
cat("Ceiling value:", y, "\n")

Output:-

Original value: 3.7 
Ceiling value: 4 

Explanation:

  • To round a number up to the closest integer in R, use the ceiling() function.
  • For instance, the integer 4 will be returned by ceiling(3.7).
  • The ceiling() function is used to round up the x value, which is 3.7, to the nearest integer, which is 4.

5. Conversion method:

Using R’s as.integer() function, this technique directly transforms a numeric value to an integer value. As an illustration, integer 3 will be returned by as.integer(3.7).

Code:-

# Generate a random numeric value
x <- 3.7

# Apply conversion method
y <- as.integer(x)

# Print output
cat("Original value:", x, "\n")
cat("Converted value:", y, "\n")

Output:-

Original value: 3.7 
Converted value: 3 

Explanation:

  • A random numeric value of 3.7 is assigned to the variable x.
  • The as.integer() function is applied on x to explicitly convert it to an integer value.
  • The converted value is stored in a new variable y.
  • The cat() function prints the original and converted values in the console.

Best Approach

If we have to choose one best approach overall to convert numeric to integer in R, then using the as.integer() function would be the most recommended approach. Here are some reasons why:

  • Performance: The as.integer() function is the fastest approach to converting numeric to integers. It is implemented in C and is highly optimized, making it faster than other R-based solutions.
  • Simplicity: The as.integer() function is very easy to use and requires minimal code. It takes a numeric value as input and returns an integer value. It is also a built-in function in R, which means that it is available by default without requiring additional packages or libraries.
  • Consistency: Using as.integer() ensures that the resulting integer value is consistent with how R handles integers. R uses 32-bit integers, so using this method ensures that the resulting value will be within the range of 32-bit integers.
  • Compatibility: The as.integer() function is compatible with other R functions and packages. It can be used in data manipulation and analysis, and it is also supported by various data visualisation libraries such as ggplot2 and lattice.

Sample Problems

Sample Problem 1:

How can we calculate the total sales in dollars and cents for a given sales data in dollars for the current quarter?

Solution:

  • Defined the sales data for the current quarter using the c() function, which creates a vector of values. In this case, the vector contains four numeric values representing the sales amounts for each of the four months in the quarter.
  • Assign this vector to the variable sales. Calculate the total sales in cents by multiplying each sales amount by 100 (to convert dollars to cents), then summing the resulting values using the sum() function.
  • Assign the result of this calculation to the variable total_sales_cents.
  • Convert the total sales from cents to dollars and cents by dividing the total sales in cents by 100.
  • Assign the result of this calculation to the variable total_sales_dollars.
  • Use the cat() function to print out the original sales data, the total sales in cents, and the total sales in dollars, each on a separate line.
  • The “\n” character is used to add a line break after each piece of output so that the next line is printed on a new line.

Code:-

# Define the sales data for the current quarter
sales <- c(1023.56, 4567.89, 3123.45, 5678.91)

# Calculate the total sales in cents
total_sales_cents <- trunc(sum(sales * 100))

# Convert the total sales to dollars and cents
total_sales_dollars <- total_sales_cents / 100

# Print the original sales data, total sales in cents, and total sales in dollars
cat("Sales data:", sales, "\n")
cat("Total sales in cents:", total_sales_cents, "\n")
cat("Total sales in dollars:", total_sales_dollars, "\n")

Output:-

Sales data: 1023.56 4567.89 3123.45 5678.91
Total sales in cents: 1399441
Total sales in dollars: 13994.41

Sample Problem 2:

How to convert decimal temperature data to integer format in R, and print both the original and converted data?

Solution:

  • Start by generating a sample temperature data in decimal format. We then convert this data to integers using the as.integer() function in R.
  • Here, multiply the temperature data by 10 before converting it to integers, which will allow us to retain the precision up to the first decimal place.
  • Then print the original temperature data and the temperature data in integer format using the cat() function in R.
  • This is just one example of how converting numeric values to integers can help achieve higher precision and accuracy in scientific calculations.

Code:-

# Generate temperature data in decimal format
temp <- c(25.7, 26.3, 24.9, 26.1, 25.4)

# Convert temperature data to integers
temp_int <- as.integer(temp * 10)

# Print original temperature data
cat("Original Temperature Data: ", temp, "\n")

# Print temperature data in integer format
cat("Temperature Data in Integer Format: ", temp_int, "\n")

Output:-

Original Temperature Data:  25.7 26.3 24.9 26.1 25.4
Temperature Data in Integer Format:  257 263 249 261 254

Sample Problem 3:

How do the temperature and precipitation values of a sample dataset relate to each other?

Solution:

  • Create two vectors temp and precip to hold temperature and precipitation data.
  • Use the round() function to convert each temperature value to the nearest integer.
  • The rounded values are stored in the temp_int vector. Calculate the average temperature by taking the mean of the temp_int vector.
  • Use the round() function to convert each precipitation value to the nearest integer.
  • The rounded values are stored in the precip_int vector.
  • Calculate the total precipitation by summing the values in the precip_int vector.
  • Use the cat() function to output the average temperature and total precipitation, each on a separate line.
  • The “\n” character is used to add a line break after the average temperature output.

Code:-

# create sample data
temp <- c(25.6, 23.7, 27.9, 22.1, 24.8)
precip <- c(12.3, 8.9, 15.6, 10.2, 9.8)

# convert temperature values to integer using rounding method
temp_int <- round(temp)

# calculate average temperature
avg_temp <- mean(temp_int)

# convert precipitation values to integer using rounding method
precip_int <- round(precip)

# calculate total precipitation
total_precip <- sum(precip_int)

# output results
cat("Average temperature:", avg_temp, "\n")
cat("Total precipitation:", total_precip)

Output:-

[1] "Maximum temperature: 70°F"
[1] "Minimum temperature: 45°F"

Sample Problem 4:

How to convert decimal values of glucose levels to integers?

Solution:

  • A dataset of blood glucose levels of patients measured in milligrams per deciliter (mg/dL) and we want to convert these values to integers for more accurate analysis.
  • Use the round() function to round the numeric values to the nearest integer and then cast them to integers using the ceiling() function.
  • First define a sample dataset glucose consisting of blood glucose level measurements in mg/dL.
  • Then use the round() function to round the values to the nearest integer and assign them to a new variable glucose_int.
  • Finally, print the original and converted values using the cat() function.
  • The output shows the original and converted blood glucose level measurements, with the converted values being integers rounded to the nearest whole number.
  • This can help increase the accuracy of medical data analysis and aid in making informed decisions.

Code:-

# Sample data
glucose <- c(125.8, 98.2, 150.3, 110.6, 90.1, 135.5)

# Convert to integers using ceiling method
glucose_int <- ceiling(glucose)

# Print original and converted values
cat("Original values:", glucose, "\n")
cat("Converted to integers:", glucose_int, "\n")

Output:-

Original values: 125.8 98.2 150.3 110.6 90.1 135.5
Converted to integers: 126 98 150 111 90 136

Sample Problem 5:

How does rounding a dataset to integers affect the mean and standard deviation?

Solution:

  • Generate a dataset of 100 random decimal numbers between 0.1 and 10 using the runif() function.
  • Use the mean() and sd() functions to calculate the mean and standard deviation of the dataset, respectively, and store the results in the mean_val and sd_val variables.
  • Use the cat() function to print the original mean and standard deviation values to the console.
  • Convert the dataset to integers by multiplying each value by 100 and rounding it to the nearest integer using the round() function.
  • The resulting integer dataset is stored in the int_dataset variable. Use the mean() and sd() functions again to calculate the mean and standard deviation of the integer dataset, respectively, and store the results in the int_mean_val and int_sd_val variables.
  • To obtain the correct mean and standard deviation of the original decimal dataset, divide the integer mean and standard deviation by 100.
  • Use the cat() function again to print the integer mean and standard deviation values to the console.

Code:-

# Generate dataset
set.seed(123)
dataset <- runif(100, 0.1, 10)

# Calculate mean and standard deviation
mean_val <- mean(dataset)
sd_val <- sd(dataset)

# Print results
cat("Mean value:", mean_val, "\n")
cat("Standard deviation:", sd_val, "\n")

# Convert dataset to integers and recalculate mean and standard deviation
int_dataset <- round(dataset * 100)
int_mean_val <- mean(int_dataset) / 100
int_sd_val <- sd(int_dataset) / 100

# Print results
cat("Integer Mean value:", int_mean_val, "\n")
cat("Integer Standard deviation:", int_sd_val, "\n")

Output:-

Mean value: 4.927758
Standard deviation: 2.762146
Integer Mean value: 4.92
Integer Standard deviation: 2.75

Conclusion

The importance of converting numeric data to integers in R for improved computation accuracy in various applications. It explores different methods, including the as.integer(), trunc(), round(), floor(), and ceiling() functions, and concludes that the as. integer() function is the most effective and straightforward way to convert numeric to an integer.

The article offers real-world scenarios, such as financial computations, scientific calculations, climatic data analysis, medical data analysis, and statistical analysis, where converting numeric to integer is essential.

The article includes sample R code for each scenario and emphasises the benefits of memory conservation and better accuracy in mathematical operations on whole integers.