ord() and chr() in Python
Name:
Date:
Class:
A
Quick Questions
Shade in the A or B circle for each question.
1. What does ord("A") return in Python?
2. What does chr(66) return?
3. Which function changes a letter into a number?
4. Which function changes the number 72 into the letter "H"?
5. Which line gives the position 0-25 of the letter "D" in the alphabet?
B
Match the Pairs
Draw a line connecting each item on the left to its match on the right.
| Left column | Right column | |
|---|---|---|
| 1ord("A") | Achr(2 + ord("A")) | |
| 2chr(66) | Bord("D") - ord("A") | |
| 3Convert a letter into a position from 0 to 25 by taking away the code of "A" | Cord() needs a character such as "A", not a number. To turn 65 into a letter, use chr(65). | |
| 4Turn a position from 0 to 25 back into an uppercase letter by adding the code of "A" and using chr() | Dchr() needs a number code such as 65, not a letter. To get the code of "A", use ord("A"). | |
| 5ord(65) | EReturns the character for the number code 66, which is "B" | |
| 6chr("A") | FReturns the number code of the character A, which is 65 |
C
Definitions
ord() and chr()
D
Fill in the Blanks
Complete each line of code by filling in the missing parts.
1.
print(___("A"))
2.
print(___(65))
3.
pos = ord("D") - __
print(pos)
4.
letter = "C"
num = ord(letter) - 65
print(___)
5.
print(chr(ord("A") _ 1))
E
Spot the Error
Shade in the letter of the line that contains an error.
Question 1
A
letter = "A"
B
code = chr(letter)
C
print(code)
Question 2
A
word = "HI"
B
first = word[0]
C
code = ord(word)
D
print(code)
Question 3
A
pos = ord("C") + 65
B
print(pos)
C
print(chr(pos + 65))
Question 4
A
pos = 5
B
code = pos + 65
C
letter = ord(code)
D
print(letter)
Question 5
A
letter = "Z"
B
pos = ord(letter) - 64
C
print(pos)
Answer Key
ord() and chr() in Python
Section A: Quick Questions
Q1
A — 65
Q2
A — "B"
Q3
A — ord()
Q4
B — chr(72)
Q5
B — ord("D") - 65
Section B: Match the Pairs
Q1
ord("A") → Returns the number code of the character A, which is 65
Q2
chr(66) → Returns the character for the number code 66, which is "B"
Q3
Convert a letter into a position from 0 to 25 by taking away the code of "A" → ord("D") - ord("A")
Q4
Turn a position from 0 to 25 back into an uppercase letter by adding the code of "A" and using chr() → chr(2 + ord("A"))
Q5
ord(65) → ord() needs a character such as "A", not a number. To turn 65 into a letter, use chr(65).
Q6
chr("A") → chr() needs a number code such as 65, not a letter. To get the code of "A", use ord("A").
Section C: Definitions
Q1
ord() and chr() — ord("A") returns the number code of a character (65). chr(65) turns a number code back into its character ("A"). Ciphers use them to change letters to numbers and back.Section D: Fill in the Blanks
Q1
print(ord("A"))Q2
print(chr(65))Q3
pos = ord("D") - 65
print(pos)Q4
letter = "C"
num = ord(letter) - 65
print(num)Q5
print(chr(ord("A") + 1))Section E: Spot the Error
Q1
B — chr() turns a number into a character, so it cannot take the letter "A". To get the number code of a letter, use ord(letter).
Q2
C — ord() only accepts a single character. Passing the whole string "HI" causes a TypeError. It should be ord(first), which is the single letter "H".
Q3
A — To turn a letter into a position from 0 to 25, subtract 65 (the code for "A"). Adding 65 gives 132 instead of 2. It should be ord("C") - 65.
Q4
C — ord() changes a character into a number, but code is already a number. To change a number code into a letter you need chr(code).
Q5
B — "A" has code 65, so subtract 65 to start counting at 0. Subtracting 64 makes Z equal 26 instead of 25. It should be - 65.