Lecture #15

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- Hour exam Friday; Review Today

R E V I E W T O P I C S

HyperText Markup Language (HTML)

Linked Property Makes WWW What it is Today
HTML Structures
Tags (Note: The tags are case insensitive)
Ordered Lists; Unordered Lists
Tables
Links (Anchors)
Text Formatting
Carriage Returns
Images

An Introduction to Programming: Coding Decision Trees

Object Oriented Programming
- Class Describes an Object in Java
Two Ways of Using Java
- Using Web with an Applet (for this class)
Example: "Hello World", Things to Note:
- Program tested with Web Browser or appletviewer
Demonstrate Use of Buttons; Important Pieces:
- if statements
String Variables
Reading Data Into Your Program: Input
- Example: Read In and Duplicate Demo .getText
If Statements; If - Else Statements
Logical Expression
Assignment Statement
Method Invocation
Using Decisions to Solve Problems
Example: A Number Guessing Game
- Binary Search
Decision Trees
Example: Car Diagnosis Problem: Decision Tree
- Review Code Noting myLocation Variable
Using Primitive Data Types: Integers
Example: Doing Multiple Tallies

Strings and String Manipulation

The String Class

Declaration: String message;
String Constant: "Good Morning World!"
String Assignment: message = "It's Friday";
String Class Has Many Methods for Manipulation
- String substring(int start, int end)
Exchanging the Contents of Two Variables
- An Algorithm: The Exchange Problem

More About Syntax


 <name> -> any string of alphanumeric symbols that begins with a letter
 <statement> -> <name> = <expression> ;
 <statement> -> <name> = new <class>(<arguments>) ;
 <statement> -> <name>.<method>(<arguments>)|<method>(<arguments>);
 <arguments> -> possibly empty list of <expression>s separated by commas
 <expression> -> <string-expression> | <int-expression> | <oth-expression>
 <string-expression> ->  <string-expression> + <string-expression>
 <string-expression> ->  <string>
 <string> -> " any sequence of characters " 
 <string> -> <name>

Compound statement requires more:

11. <method> -> setText | getText | getInt | setInt | add |
                                       actionPerformed | init

12. <compound-statement> -> {
                                                           list of <statement>s
                                                  }

13. <statement> -> if (<bool-expression>)
                                         <compound-statement>

14. <statement> -> if (<bool-expression>)
                                         <compound-statement>
                               else
                                         <compound-statement>

Numerical Computation & Study of Functions

New Classes for Numbers

    public IntField(int size);
    public void setInt(int number);
    public int getInt();
    public DoubleField(int size);
    public void setDouble(double num);
    public Double getDouble();

Iteration by Button Pushing
The while Loop
Example: Redesign of Diamond Program
Arrays
- Often Use Arrays in a Loop
Array Creation and Use
Setting it Up an Array

double weights[];
weights = new double[50];
double weights[] = new double[50];
Subscript Range Errors
Example: Simple Statistics Program Design
- Display
Algorithms for Extrema
Algorithm for Mean