The document summarizes key points from a lecture on software programming. It discusses the five steps of programming: specification, design, coding, testing, and maintenance. It also covers different programming languages from machine language to natural languages. Object-oriented programming and visual programming are introduced as well. Common programming languages mentioned include C++, Python, and .NET.

1. Lecture 10
Software Programming
Microsoft
.Net
Basic
C++PerlC Python
Pascal
Cobol

2. Today’s lecture outline

3. Programming-
a five step
procedure
1 Specification
Design
Programming
Debugging
Testing

4. Programming specification
1st
Program solving the problem
Problem
Programmer
A program is used to solve a problem

5. Programming specification
Computer has to be precisely told what
it needs to do; otherwise:

6. Program design
2nd
Algorithm:
 Set of finite steps that solves a problem
 Algorithms are of many types
Algorithms may be classified into:
1. Optimal algorithms
(solves the problem to give the ‘best’ result)
2. Non-optimal algorithms
(may or may not provide acceptable results)

7. Program design
Classes of algorithm (non-exhaustive):
1. Deterministic vs. non-deterministic;
2. Exact vs. approximate algorithms;
3. Optimal vs. non-optimal algorithms;
Some algorithmic design paradigm:
1. Divide and Conquer algorithms;
2. Probabilistic algorithms;
3. Greedy algorithms; many others.

8. Program design
Heuristics:
 Set of steps that usually solves a problem;
 Solution may be non-optimal;
 Good heuristics provide non-optimal but
acceptable solution for difficult problems;
 Used when optimal algorithms are
complex/ non-existent.

9. Program design
components of design process:
1) Macro planning: high-level program
logic; (modularization)
2) Micro planning: the detailed planning;
(how to implement logic)
What to do?how to do it?

10. Hierarchy Chart
Program design
Program’s logical structure:
1. Top-down design
2. Logical hierarchy
3. Modularization
Modules:
1. Manageable size,
2. Defined input/ output

11. Program design
Program’s design details:
2 ways to show details:
i) Pseudocode: describes logic and
processing flow in human-language
statements
ii) Flow chart: graphically represents
logic flow.
Most projects use both methods

12. Program design
START
STOP
INPUT
OUTPUT
CONNECTOR
FLOW LINES
STOP
inputCent
centigrade
calcFah
fahrenheit = (1.8*centigrade) + 32
outputFah
fahrenheit
STARTConvert
Centigrade to
Fahrenheit
PSEUDOCODE:
Display “Enter Centigrade: "
Input centigrade
fahrenheit = 1.8 * centigrade + 32
Display “Centigrade to Fahrenheit = " fahrenheit

13. Program design
Source Code
Hierarchy chart
Flow chart
Pseudo Code
Machine Code
Program
Designing

14. Program coding
3rd
1) Select the appropriate programming
language
2) Follow the Syntax of the chosen
programming language

15. Program coding paradigms
1)Structured Programming:
also called procedural programming
because it uses functions or procedures
Benefits:
 reuse code written as function
 programs are modular/ structured
2) Object Oriented Programming:
(to be covered later)

16. Common instructions
1. Input: from keyboard, file, or some device
2. Output: to display, file, or some device
3. Maths (logic): addition, multiplication, etc.
Control Structures
1. Sequence: instructions executed in sequence
2. Selection: conditional execution (if-then-else)
3. Iteration: some action repeatedly (do while)
Program coding

17. Program coding
Source Code
Hierarchy chart
Flow chart
Pseudo Code
Machine Code

18. Program testing
4th
1) Perform desk checking
2) Quality assurance
3) Debug the program
4) Run real world data

19. Program maintenance
5th
1) Prepare user documentation
2) Prepare operator documentation
3) Write programmer documentation
4) Maintain the program

20. Five generations of
Programming languages2

21. 1GL: Machine language
1st
• Written in binary
• Different for every CPU
• Used for programming
computers in the earliest
days of computers.
• Computers only understand this language

22. 2GL: Assembly language
2nd
LOAD BASEPAY
ADD OVERPAY
STORE GROSSPAY
• Symbolic representation of machine language.
– opcodes
– operands
– labels
• More readable to human (not computer).
add A, B 1000111000010110
• Easy to translate to machine language.
Machine languageAssembly language
Machine language
Assembly language

23. 3GL- High-level language
3rd
•Supports structured and object-oriented
programming (OOP)
•Abstracts the hardware implementation
from the programmer
•Code is reusable and portable
•May be compiled/ or interpreted

24. Program execution (C example)

25. Compilers vs. Interpreters

26. 4GL-Very high-level languages
4th
Non procedural high-level specification
language.
4GL open up the development
environment to a wider population
Examples:
Database query language: SQL;
General use: PowerBuilder;

27. 5GL- Natural languages
5th
 Algorithms do not have to be specified
 Aims to make the programmer redundant
 May not be created yet
 Will create software automatically

28. Commonly used
Programming languages3

29. Common Program Languages
Microsoft
.Net
Basic
C++
Perl
C Python
Pascal
Cobol

30. Objected-Oriented &
Visual Programming4

31. Object Oriented Programming
 Also called OOP
 Intuitive method of programming
 Code reuse
 Code used in many projects
 Speeds up program development
 Simplifies program development
 Enhances structured programming

32. Object Oriented Programming
Develops objects
All real world items are objects
Contains data about the item
Contains functionality
Object encapsulates both into one package

33. Visual Programming
Programming is done using a graphical
interface;
No actual coding is done;
Code is generated through specification of
functionality using menus and graphical
manipulation of program elements;
Intended to be user friendly.

34. Today’s lecture summary

35. http://tinyurl.com/5hb8pp