This Python If...Else lesson is for a beginner. Read the short notes, run each example, then change one name or number and run it again.
if runs a block when the test is true. elif tries another test. else runs when every test above it failed.
The blocks are indented. A colon is required at the end of each test line.
Example 1: Start here
One if with several elif lines is clearer than nested if statements.
score = 82 # a whole number
if score >= 90: # run the indented lines only when this is true
band = "A" # text
elif score >= 75: # checked only when the tests above were false
band = "B" # text
else: # runs when the test above was false
band = "C" # text
print(band)
Example 2: Two branches
Exactly one branch runs.
score = 82 # a whole number
if score >= 80: # run the indented lines only when this is true
print("Pass")
else: # runs when the test above was false
print("Try again")
Example 3: Three branches
elif is checked only when the earlier tests were false.
score = 74 # a whole number
if score >= 80: # run the indented lines only when this is true
print("Pass")
elif score >= 60: # checked only when the tests above were false
print("Revise")
else: # runs when the test above was false
print("Restart")
Example 4: A test with and
Both parts must be true.
score = 82 # a whole number
submitted = True # True or False, not text
if score >= 80 and submitted: # run the indented lines only when this is true
print("Accepted")
One if with several elif lines is clearer than nested if statements.
