3. Introduction to basic Python constructions

This section contains an introduction to some basic programming concepts, and the basic Python constructions that implement them. It is intended primarily for those with no programming background, but there are fine points (such as the list comprehension section) which should be of help to any newcomer to Python.

What we know so far:

1. Some types that can be data and contain data

2. Some ways to put data in containers and take it out

What we can’t do yet:

1. Branch: do different things depending on current conditions, including current data item;

2. Do things over and over, as a way of computing complex things;

3. Package things up into reusable code.

Contents

• 3.1. If-then construction (Conditionals)
• 3.2. Operators that return Boolean results
• 3.3. How Boolean tests work
  • 3.3.1. The special case of None
  • 3.3.2. Python: expressions versus statements
  • 3.3.3. Conditional expressions
• 3.4. Loops
  • 3.4.1. While loops
  • 3.4.2. For loops
  • 3.4.3. Filtering with for loops
  • 3.4.4. Nested loops
  • 3.4.5. A better example of a while loop
  • 3.4.6. Shortcuts for updating var values
  • 3.4.7. Tuple assignments and iterating through pairs
  • 3.4.8. Loop keywords: continue and break
• 3.5. List comprehension
  • 3.5.1. Basic comprehensions
  • 3.5.2. Conditional comprehensions
  • 3.5.3. Nested Comprehensions
  • 3.5.4. Examples from Norvig’s sudoku solver
  • 3.5.5. Set comprehension
• 3.6. Functions
  • 3.6.1. Reasons for using functions
  • 3.6.2. Further examples
• 3.7. Functions, loops, and types assignment
  • 3.7.1. Exercise 1
  • 3.7.2. Exercise 2
  • 3.7.3. Exercise 3
  • 3.7.4. Exercise 4
  • 3.7.5. Exercise 5
  • 3.7.6. Exercise 6
  • 3.7.7. Exercise 7
  • 3.7.8. Exercise 8
  • 3.7.9. Exercise 9
  • 3.7.10. Exercise 10
  • 3.7.11. Exercise 11
• 3.8. Nims assignment
• 3.9. Combination
• 3.10. Recursion (advanced)
• 3.11. Student scholarship problem
• 3.12. Permutation (advanced)
  • 3.12.1. Combinations
• 3.13. Summary
• 3.14. Midterm