Calculus & Numerical Methods
Lagrange Interpolation
Interpolate at x from sample points.
Formula
Formula
p(x) = Σ yj Lj(x)
Variables
| Symbol | Definition | Type & range | Units | Role |
|---|---|---|---|---|
| xs | sample x values | list of real numbers | — | input |
| ys | sample y values | list of real numbers | — | input |
| x | query | real number (ℝ) | — | input |
Try it yourself
Interactive calculator
Worked examples
Example 1
Givenx values = 0, 1, 2, y values = 1, 3, 7, x = 1.5
Result4.75
Example 2
Givenx values = 0, 2, 4, y values = 0, 4, 16, x = 3
Result9