Project 1 -- now three late days, if turned in today...

Late Days (re-visited)
 

CS151 -- Administration

Project 2  -- mailing list, today, probably this afternoon.

Quiz 1

Mean ~= 37
Grades:  Top Score 48, as mean was 37 (C+), no curve...
A = [48-44]     8
B = [43-39]     12
C = [38-34]     14
D = [33-29]     8
F =  [28-0]       5

Functions

Purpose

• Encapsulation
• Separation of ideas

Functions

Scope

• Not mouthwash!!! ;-)
• How long a variable is visible, and exists
• Effectively how long you can use a variable

Functions

Scope

• Global

Functions

Scope

• Global
• Visible everywhere in the program
• Declared outside EVERY block!
• Just declare the variable, nothing special...

Functions

Scope

• Global
• Static -- the three meanings...

Functions

Scope

• Global
• Static -- the three meanings...
• uses special static keyword:

  static double myNumber;

Functions

Scope

• Global
• Static -- the three meanings...
• static on global variables to limit scope

Functions

Scope

• Global
• Static -- the three meanings...
• static in a block, functions only
• continues to exist, not re-allocated every function execution.

Functions

Scope

• Global
• Static -- the three meanings...
• In a class member variable
• all objects of that class share one variable

Functions

Scope

• Global
• Static -- the three meanings...
• Local

Functions

Scope

• Global
• Static -- the three meanings...
• Local
• Only visible in their current block
• when execution leaves the block, de-allocated

Functions

Scope

• Global
• Static -- the three meanings...
• Local
• Blocks

Functions

Scope

• Global
• Static -- the three meanings...
• Local
• Blocks
• Everything between { and }
• when you exit a block normally (return or execution steps out of a block) all variables of the block are de-allocated.
• frames of execution

Classes

User defined data type

Terminology
 

Classes

User Defined Type

• Allows you to make a new type...
• combination of other types
• nothing REALLY new...

Classes

Terminology

• class
• abstract
• object
• instance

Classes

Terminology

• class
• abstract
• There is some type of thing called a person...

Classes

Terminology

• object
• instance
• Joe is a person

Classes

Usage

• declaration:
• className variableName;
• iostream cout;
• fstream fout;
• string myString;

Classes

Usage

• declaration:
• className variableName;