1. Introduction to Computer Programming
ISM 3005 Course Introduction
Introduction to Computer Programming
Exercise #1
Exercise #2
6 Program Development Steps
Program Design as an Art
Typical Beginner Problems
Six Computer Operations
Summary
Demonstration 2

2. Computers & Organizations
The first rule of any technology used in a business is that automation applied to an efficient operation will magnify the efficiency. The second rule is that automation applied to an inefficient operation will magnify the inefficiency. Bill Gates

3. Exercise #1
(Who’s The Dummy Now?)

4. Exercise #2

5. Exercise (cont.)
Were you correct (would your instructions have given a correct answer)?
If not, why?
Didn’t know a step?
Forgot to include a step?
You thought you knew the steps but were wrong?
Calculations were wrong?
This part of programming is where the majority of problems occur… … but it has nothing to do with computers or code

6. Six Program Development Steps
Analyze: Define the problem
Design: Plan a solution
Choose the Interface: What will the user see and do?
Code: Translate the solution into programming language
Test and Debug the Program: Find program and logic errors
Complete the Documentation: Finish what you should have been working on all along

7. Defining the Problem
Ensuring that the programmer is working on the correct problem
Users notorious for not clearly stating the problem to be solved or desired results
Ensuring that the programmer understands the problem itself
Domain-specific knowledge need for the solution
User-specific terminology
Avoid wasting time on false starts or the wrong problem

8. Defining the Problem: Example
The instructor’s policy is to adjust each person’s score upward so that the highest score becomes 100 and all other scores are adjusted to be their percentage of the high score.
Grades are currently stored in a sequential data file with the student’s SSN followed by their raw score followed by the next student’s SSN . . .
What is your task? Is it clearly stated? Can you infer it? What is the formula for each student’s adjusted score?

9. Design
Identifying the major steps in the solution
Where will data be and how will it be structured?
Which screens will be needed and what will they do?
What information must the user provide?
What processing must the computer do and in what sequence?
What outputs must the program create?
Design is the most fundamentally important step in system creation (and the one that pays the best)

10. Design (cont.)
Use an Input - Processing - Output model approach
What is the output of the program?
What inputs are available or needed?
What processing will transform the inputs into the outputs?
Avoid getting bogged down in details (until later)
Outline the solution as if pencil, paper, and 3x5 index cards are the only tools available
Don’t start programming until you understand what you are trying to accomplish!

11. Design: Example
The solution will have three major steps which must be accomplished in order
1 Read the file to find the highest score
2 Calculate the amount of the curve
3 Update each record by performing the calculation on it and saving the score
Each of these steps will have further specific sub- steps to be accomplished
How would you do this if all scores were on 3x5 cards?

12. Choose the Interface
The interface is the way the program looks to the user
Focus on the tasks as the user perceives them
Give each logical step in the process its own portion of the interface
Screen
Section of a screen

13. Choose the Interface (cont.)
What interface elements would be needed for our sample problem?
What interface elements would be needed if we expand the scope of the problem to include data collection as well as final grade calculation?

14. Code the Solution
Translate the solution design into specific code
Programming (as opposed to design) is primarily a process of putting familiar elements into a different order
Like constructing a new paragraph with old words
Recognize the program elements identified in the design step
Recognize the programming elements available in the language
Match the programming elements with the design needs and modify for the circumstances

15. Test and Debug
Test the program for several factors
Language errors
Logic errors
Use test data with known results
Compare computer results with test results
Run-time errors—Errors that occur with certain combinations of data
Test the extreme values
First and last elements
Highest and lowest possible values
Anything a user could possibly do

16. Test and Debug (cont.)
Test and debug small chunks of code
Save and then run your program regularly (Rule of thumb: after every five lines or so)
If the program worked Then you write five lines of code Now it doesn’t work Where do you think the problem is?

17. Complete the Documentation
Documentation must take place at every step in the process
Database design
Solution development
Algorithm development
Coding
Document as you GO! Don’t wait until you are finished
Document your design in your code
Documentation will be very heavily weighted in this course

18. Program Design as an Art
Most of the previous steps require analysis
Steps will not be implemented as rules that apply in every case
Programmer brings experience with patterns of program flow and structure to bear on new problems
Introducing these patterns is a major objective of this course

19. Program Design as an Art (cont.)
Programmer must have the ability to communicate
Programmer must be able to recognize when a language capability is applicable to an algorithm need
There is often more than one correct answer!!

20. Typical Beginner Problems
You cannot look for the correct answer to your programming challenge in a reference
Each problem is new (or we’d use the existing solution)
You must figure out the solution to the problem before you start coding!
You must decompose big problems into steps
Repeat until there are nothing but little problems
Then solve the little problems
Learn the mechanics of managing your project files. Practice them and back up your files!!

21. Six Computer Operations
Computers can perform six fundamental tasks
Receive information from various sources
Output information in various ways
Print or screen
Permanent storage
Perform arithmetic
Assign values to variables (temporary storage)
Make choices based on compared values
Repeat (iterate) actions
Programs are constructed by building code segments around these capabilities

22. Six Computer Operations (cont.)
Programming languages provide built in capabilities to accomplish the six operations
Often more than one way to do each
These are the tools in your toolbox
You must learn how to use them and when to use them
And don’t forget your focus on the underlying problem
Focus on the details (the trees)
Don’t forget the forrest

23. PRACTICE Summary You will deal heavily with Patterns Implications
Values
The exact answer is rarely in the book
Imagination, creativity, and experience are key
This class helps with experience
Imagination and creative are in your arena
PRACTICE