Outline for January 23, 2019

Reading: §4

1. Functions [hello.py]
   1. What functions are
   2. Defining them
   3. Using them
2. Quick look at using them [quad.py]
   1. Passing values to functions
   2. Returning values from functions
3. In more detail: passing values to functions [args.py]
   1. Formal parameters in subject definition
   2. Actual parameters (arguments)
   3. Matching arguments to formal parameters
   4. Local variables
4. In more detail: how Python does function calls [quad.py]
   1. Caller suspends execution at point of call, remembers where it left off
   2. Formal parameters assigned values from actual parameters
   3. Execute function body
   4. Return control to where caller left off
5. Refactoring code
   1. Compute the perimeter of a triangle [peri0.py]
   2. Collapse similar statements: make the distance between 2 points a function [peri1.py]
   3. Collapse similar statements: make the prompts a function [peri2.py]
   4. Refactor for clarity only: make the perimeter computation a function [peri3.py]
   5. Add error checking: “peri0.py” done right [peri-c.py]
6. Add error checking: “quad.py” done right [quad-c.py]

Matt Bishop Department of Computer Science University of California at Davis Davis, CA 95616-8562 USA

Last modified: Version of January 22, 2019 at 6:24PM Winter Quarter 2019 You can get a PDF version of this