PLANNING THE COMPUTER PROGRAM

•  The Programming Process – Purpose

Understand the problem

• Read the problem statement
• Question users
• Inputs required
• Outputs required
• Special formulas
• Talk to users

Plan the logic

• Visual Design Tools
• Input record chart
• Printer spacing chart
• Hierarchy Chart
• Flowchart
• Verbal Design Tools
• Narrative Description
• Pseudocode

Code the program

• Select an appropriate programming language
• Convert flowchart and/or Pseudocode instructions into programming language statements

Test the program

• Syntax errors
• Runtime errors
• Logic errors
• Test Data Set

 Implement the program

• Buy hardware
• Publish software
• Train users
• Implementation Styles
• Crash
• Pilot
• Phased
• Dual

Maintain the program

• Maintenance programmers
• Legacy systems
• Up to 85% of IT department budget

Problem solving with computers involves several steps:

• Clearly define the problem.
•  Analyze the problem and formulate a method to solve it (see also “validation”).
•  Describe the solution in the form of an algorithm.
•  Draw a flowchart of the algorithm.
•  Write the computer program.
•  Compile and run the program (debugging).
•  Test the program (debugging) (see also “verification”).
•  Interpretation of results.

 Verification and Validation

If the program has an important application, for example to calculate student grades or guide a rocket, then it is important to test the program to make sure it does what the programmer intends it to do and that it is actually a valid solution to the problem. The tests are commonly divided as follows: Verification