Flash cards
Review the key moves
What is the main idea behind Python While Loops?
Lesson checks
Practice each idea before moving on
Short Mimo-style checks built from this lesson's code, terms, and sequence.
Which statement best captures the main point of this lesson?
Complete the missing token from the example code.
___ i < 6:Put the learning moves in the order that makes the concept easiest to apply.
Python Loops
Python has two primitive loop commands
- while loops
- for loops
The while Loop
With the while loop we can execute a set of statements as long as a condition is true.
Example
i = 1
while i < 6:
print(i)
i += 1Note
remember to increment i, or else the loop will continue forever.
The while loop requires relevant variables to be ready, in this example we need to define an indexing variable, i , which we set to 1.
The break Statement
With the break statement we can stop the loop even if the while condition is true:
Example
i = 1
while i < 6:
print(i)
if i == 3:
break
i += 1The continue Statement
With the continue statement we can stop the current iteration, and continue with the next:
Example
i = 0
while i < 6:
i += 1
if i == 3:
continue
print(i)The else Statement
With the else statement we can run a block of code once when the condition no longer is true:
Example
i = 1
while i < 6:
print(i)
i += 1
else:
print("i is no longer less than 6")Note
The else block will NOT be executed if the loop is stopped by a break statement.