How to Calculate Interpolation
What is Interpolation?
Interpolation estimates values between known data points using polynomial (Lagrange) or spline methods.
Step-by-Step Guide
- 1Input known data points
- 2Choose interpolation type: linear, polynomial, spline
- 3Estimate value at desired point
Worked Examples
Input
Points: (1,2), (2,4), (3,9)
Result
At x=2.5: linear ≈ 6.5, cubic polynomial ≈ 6.5 (both smooth)
Common Mistakes to Avoid
- ✕Extrapolating beyond data range (unreliable)
- ✕Over-fitting with high-degree polynomials
Frequently Asked Questions
Which interpolation method is best?
Cubic splines usually; balance between fitting and smoothness.
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