You can use the sprintf() function in R to print formatted strings.

This function uses the following basic syntax:

sprintf(fmt, x)

where:

• fmt: The format to use
• x: The value to format

The following examples show how to use this function in practice.

Example 1: Format Digits After Decimal Point

The following code shows how to use sprintf() to only display two digits after a decimal point:

#define value
x <- 15.49347782

#only display 2 digits after decimal place
sprintf("%.2f", x)

[1] "15.49"

Example 2: Format Digits Before Decimal Point

The following code shows how to use sprintf() to display ten digits before the decimal point:

#define value
x <- 15435.4

#display 10 total digits before decimal place
sprintf("%10.f", x)

[1] "     15435"

Since there were only five digits before the decimal point to start with, the sprintf() function added another five blank spaces at the beginning of the string to make a total of 10 digits before the decimal point.

Example 3: Format Value Using Scientific Notation

The following code shows how to use sprintf() to display a value in scientific notation:

#define value
x <- 15435.4

#display in scientific notation using lowercase e
sprintf("%e", x)

[1] "1.543540e+04"

#display in scientific notation using uppercase E
sprintf("%E", x)

[1] "1.543540E+04" 

Example 4: Format One Value in String

#define value
x <- 5.4431

#display string with formatted value
sprintf("I rode my bike about %.1f miles", x)

[1] "I rode my bike about 5.4 miles"

Example 5: Format Multiple Values in String

The following code shows how to use sprintf() to format multiple values in a string:

#define values
x1 <- 5.4431
x2 <- 10.778342

#display string with formatted values
sprintf("I rode my bike %.1f miles and then ran %.2f miles", x1, x2)

[1] "I rode my bike 5.4 miles and then ran 10.78 miles"

Additional Resources

How to Use paste & paste0 Functions in R