Job Ready Python

Lesson 7Controlling Program Flow with Loops

Python supports a variety of control structures that determine how content in a program will work and interact. This lesson continues the exploration including additional control structures that make creating algorithms possible. The lesson concludes with a discussion of how iteration aids in text processing.

LEARNING OBJECTIVES

By the end of this lesson, you will be able to:

• Create a Python script that uses a for loop to repeat an activity until a specific criterion is met.
• Create a Python script that uses a while loop to repeat an activity as long as a specific criterion holds true.
• Using string operations to manipulate text.

ITERATIONS OVERVIEW

Lesson 5 introduced control structures. These structures are used to “control” the flow of data through an application. Python supports various structures through control statements of sequence, iteration, and selection. In Lesson 5 selection and progression were discussed. The sequence control structure (executed in a sequence statement) is completed one statement after the other. The selection control structure (implemented in a selection statement) executes only after a particular condition is met. Although these types of code statements allow applications to run, in most cases, using only sequence and selection statements would make for very long program code.

In this lesson, a third control structure is introduced: iteration. Iteration, along with iterative code statements, ...