3. Control Statements and Program Development

Objectives

• Decide whether to execute actions with the statements if, if…else and if…elif…else.
• Execute statements repeatedly with while and for.
• Shorten assignment expressions with augmented assignments.
• Use the for statement and the built-in range function to repeat actions for a sequence of values.
• Perform sentinel-controlled iteration with while.

Objectives (cont.)

• Learn problem-solving skills: understanding problem requirements, dividing problems into smaller pieces, developing algorithms to solve problems and implementing those algorithms in code.
• Develop algorithms through the process of top-down, stepwise refinement.
• Create compound conditions with the Boolean operators and, or and not.

Objectives (cont.)

• Stop looping with break.
• Force the next iteration of a loop with continue.
• Use some functional-style programming features to write scripts that are more concise, clearer, easier to debug and easier to parallelize<\b>.

Outline

• 3.1 Introduction
• 3.2 Algorithms
• 3.3 Pseudocode
• 3.4 Control Statements
• 3.5 if Statement
• 3.6 if…else and if…elif…else Statements
• 3.7 while Statement

Outline

• 3.8 for Statement
  • 3.8.1 Iterables, Lists and Iterators
  • 3.8.2 Built-In range Function
• 3.9 Augmented Assignments
• 3.10 Program Development: Sequence-Controlled Iteration
  • 3.10.1 Requirements Statement
  • 3.10.2 Pseudocode for the Algorithm
  • 3.10.3 Coding the Algorithm in Python
  • 3.10.4 Introduction to Formatted Strings
• 3.11 Program Development: Sentinel-Controlled Iteration

Outline

• 3.12 Program Development: Nested Control Statements
• 3.13 Built-In Function range: A Deeper Look
• 3.14 Using Type Decimal for Monetary Amounts
• 3.15 break and continue Statements
• 3.16 Boolean Operators and, or and not
• 3.17 Intro to Data Science: Measures of Central Tendency—Mean, Median and Mode
• 3.18 Wrap-Up

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©1992–2020 by Pearson Education, Inc. All Rights Reserved. This content is based on Chapter 3 of the book Intro to Python for Computer Science and Data Science: Learning to Program with AI, Big Data and the Cloud.

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