Python For Informatics Chapter 5

Front 1

while statement

Back 1

Same as English meaning.

n = 5
while n > 0:
print n
n = n-1
print 'Blastoff!'

“While n
is greater than 0, display the value of n and then reduce the value of n by 1. When
you get to 0, exit the while statement and display the word Blastoff!”

Front 2

loop

Back 2

When the code looks back around to the to. Each time we execute the body of the loop, we call it an iteration.

Front 3

iteration variable

Back 3

The variable that changes each time the loop executes and controls when the loop finishes. Without the iteration variable you will have a infinite loop.

Front 4

continue statement

Back 4

You can use the continue statement to skip to the next iteration without finishing the body of the loop for the current iteration.

Returns back to top of loop.

Front 5

while vs for

Back 5

While statement is indefinite loop because it simply loops until some condition becomes False.

The for loop is looping through a known set of items so it runs through as many iterations as there are items in the set. Often used for list of things to loop through.

Front 6

loops are generally constructed by:

Back 6

• Initializing one or more variables before the loop starts.
• Performing some computation on each item in the loop body, possibly
changing the variables in the body of the loop.
• Looking at the resulting variables when the loop completes.

Front 7

break statement

Back 7

Used to jump out of a loop.