5.8: Common Mistakes and Best Practices
- Page ID
- 136643
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Common Mistake |
How to Fix It |
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Using = instead of == in a condition. |
Use == when comparing values. Use = only for assignment. |
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Forgetting the end statement. |
Every if, switch, for, and while block needs a matching end. |
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Writing conditions that do not cover all possible inputs. |
Use else or otherwise to handle unexpected cases. |
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Using & or | with complicated scalar conditions and getting confusing results. |
Use parentheses. For scalar true/false checks, consider && and ||. |
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Comparing text with ==. |
Use strcmp or strcmpi for character vectors and strings when appropriate. |
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Checking too late for invalid input. |
Validate input before using it in equations that may fail or produce meaningless results. |
When debugging branches, it is often helpful to print temporary messages inside each branch. For example, you can place disp("Entered first branch") inside an if statement to see whether MATLAB is entering that section of code.