.Open CS320/07 Data Types and Data Structures
.Table
.Row Prev	06 Names   Chapter 5  sections 1  to10     lab06 C/C++ Scoping
.Row Today	** Project Phase 1 	UML of old+Proposed changes(10 pts)
.Row Today	07 Data Types      Chapter 6  not section 8(unions)        lab07 C/C++ Data
.Row Next	08 Expressions  etc        Chapter 7  not section 8        lab08 C/C++ Expressions
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. Project Phase 1 Due in at start of class
.See ./projects.html#Project Phase 1 due class 07
. Preparation
1. Study chapter 6 together with the notes on UML below.

2. Answer review questions at end of chapter 6 .

3. Hand in 3 or more answers to review questions.

. Notes
Standard C++ comes with a large library (the STL) of powerful data types. 

CSCI 330 (Data Structures) is an in depth study of this material.

. Decimal Data Types
Decimal data is a very important data type becuase it is used to represent
.Key money.
Accountants require precise decimal arithmetic -- to avoid fraud.
. UML and Data Types
The UML has four primitive data types: Real, Integer, Boolean, String.

.Key Enumerations in the UML
(6.4.1) are written:
.As_is   enum{ value1, value2, ...}
in the OCL and `stereotyped` as
.As_is 		<<enumeration>>
in UML2.0.  Their values are written
.As_is           #Value1, #Value2, ...

In place of array(6.5) we have multiplicities(0..*, 4..5, ...) Put them on
attributes in square brackets and links. There are also special Object 
Constraint Language types: Collection, Set, Bag, and Sequence.

Record types(6.7) are UML classes with no operations and all attributes 
public. Composition is a good way to show fields in a record.

.Image 07uml3.gif Fields in a Record

Unions(6.8) are best treated by generalizations (multiple inheritance).

Pointers(6.9) have no special UML type. Do not use "*" to indicate pointers in the UML! The 
aggregation link is the old way (shown below) for saying that one type of data has a pointer
that refers to an object of another type. Make sure that (1) the name of 
the pointer is the role, (2) there is an arrow head, and (3) the 
multiplicity is 0..1.  However, aggregation is not really intended
to model pointers.  Modern UML users just use an association with an arrow to show a pointer.

.Image 07uml2.gif Using Aggregation to model pointers

. Chapter 6 in the UML
.Image 07uml1.gif Concepts in Chapter 6

. Class Work
.See http://www/dick/cs320/07q.html

.Close
. Lab Work
.See ./lab/07.html
. Next: Expressions
.See ./08.html