Understanding Decision-Making in Algorithms
- Decision-making is a fundamental aspect of programming that involves choosing between different actions based on specific conditions.
- It allows algorithms to adapt to varying inputs and scenarios, making them more flexible and efficient.
Note
Formally, it is called selection.
Analogy
- Think of decision-making in algorithms like choosing a route on a GPS.
- The system evaluates traffic conditions and suggests the best path, adapting in real-time to changes.
When Is Decision-Making Required?
- Conditional logic: When an algorithm needs to perform different actions based on specific conditions.
- Alternative procedures: When multiple paths or solutions exist, the algorithm must choose the most appropriate one.
- Error handling: When unexpected inputs or situations require special handling to prevent failures.
Hint
- When analysing a problem, look for keywords like "if," "when," or "unless."
- These often indicate decision points in the algorithm.
Example
- Consider a program that solves quadratic equations.
- Decision-making is required to handle different cases based on the discriminant ($D$):
- If $D > 0$: Two real solutions.
- If $D = 0$: One real solution.
- If $D < 0$: No real solutions.
Practical Guide to Constructing Conditions
- Conditions are Boolean expressions that evaluate to either true or false.
- They form the basis of decision-making in algorithms, allowing programs to choose different paths based on specific criteria.
Note
In computer science, conditions are often expressed using Boolean logic, which includes operators like AND, OR, and NOT.
To construct a more sophisticated decision-making process, conditions are often expressed using Boolean logic, which includes operators like:
- AND (&&): Returns true if both operands are true.
- OR (||): Returns true if at least one operand is true.
- NOT (!): Inverts the truth value of an operand.
Hint
So, to identify conditions in a given problem, follow these steps:
- Understand the problem: Clearly define the problem and the desired outcome.
- Identify key criteria: Determine the specific conditions that influence the decision.
- Use Boolean logic: Express these conditions using Boolean operators.
Example
Consider a traffic light system that controls pedestrian crossing:
- If the light is green, pedestrians can cross.
- If the light is red, pedestrians must wait.
Note
Conditions are used inside if statements.
Self review
- Can you identify a real-world scenario where decision-making is essential?
- Can you identify the conditions in a real-world problem and express them using Boolean logic?
- How do different Boolean operators affect the outcome of a decision?
Theory of Knowledge
- How does the use of Boolean logic in programming reflect human decision-making processes?
- What are the limitations of translating real-world scenarios into computational conditions?
