2.1 Trace Tables

Question 1

What is “Tracing Execution”?

Answer 1

A vital skill for understanding program flow and testing the accuracy of an algorithm for logic

Question 2

What do trace tables involve?

Answer 2

• Examining a printed extract of program code and running through the program
• Take each line at a time and write out in a trace table the current state of each variable
• Noting down any output the program produces
• Each variable present in the program should have its own column in the trace table
• A new row should be added under any column if the state of a variable changes

Question 3

What are trace tables good for?

Answer 3

Tracking down logic errors in a problem