String formatting with sprintf in R Programming - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of sprintf with numeric formatting

What is the output of the following R code using sprintf to format numbers?

R Programming

result <- sprintf("%.2f", 3.14159)
print(result)

A "3.14"

B "3.1416"

C "3.1"

D "3.15"

💡 Hint

Remember that %.2f rounds the number to 2 decimal places.

The format %.2f rounds the number to two decimal places. 3.14159 rounded to two decimals is 3.14.

❓ Predict Output

intermediate

String padding with sprintf

What will be the output of this R code that uses sprintf to pad a string?

R Programming

result <- sprintf("%10s", "cat")
print(result)

A "cat"

B "cat "

C " cat "

D " cat"

💡 Hint

The number 10 means the total width of the string including spaces.

The format %10s right-aligns the string in a field of width 10, padding with spaces on the left.

❓ Predict Output

advanced

Multiple values formatting with sprintf

What is the output of this R code that formats multiple values with sprintf?

R Programming

result <- sprintf("Name: %s, Age: %d, Score: %.1f", "Alice", 30, 95.678)
print(result)

A "Name: Alice, Age: 30, Score: 95"

B "Name: Alice, Age: 30, Score: 95.6"

C "Name: Alice, Age: 30, Score: 95.7"

D "Name: Alice, Age: 30, Score: 95.67"

💡 Hint

%.1f rounds the number to one decimal place.

The score 95.678 rounded to one decimal place is 95.7, so the formatted string shows that.

❓ Predict Output

advanced

Using sprintf with hexadecimal formatting

What will this R code print when formatting a number as hexadecimal using sprintf?

R Programming

result <- sprintf("%x", 255)
print(result)

A "FF"

B "ff"

C "255"

D "0xff"

💡 Hint

%x formats the number as lowercase hexadecimal without prefix.

The number 255 in hexadecimal is ff in lowercase, which %x produces without 0x prefix.

🧠 Conceptual

expert

Understanding sprintf format specifiers

Which sprintf format specifier correctly formats a floating-point number with at least 8 characters wide, 3 decimal places, and left-aligned?

A "%-8.3f"

B "%8.3f"

C "%08.3f"

D "%+8.3f"

💡 Hint

The minus sign (-) left-aligns the output in the field width.

The format %-8.3f means: floating number with 3 decimals, left-aligned in 8 spaces wide field.