Practice question · Select all that apply
Select every statement about cancellation and stability that is TRUE.
Hints
- Algebraic identity is about exact arithmetic, which is not what the machine does.
- One option offers a single knob as a cure for a structural defect.
Show the answer
- A. Conditioning describes the problem while stability describes the algorithm
- B. Subtracting nearly equal numbers can leave mostly noise
- C. Rewriting a formula to avoid such a subtraction can preserve accuracy
Why
Algebraically equal formulas can differ enormously in accuracy, that is precisely why rewriting helps, and instability is a defect of the method that no step size repairs. The other three statements are exactly as taught.
Practise Numerical Errors and Stability
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