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Tool to find an equation from its points, its coordinates x, y=f(x) according to some interpolation methods and equation finder algorithms

Answers to Questions

How to find an equation from a set of points?

To derive the equation of a function from a table of values (or a curve), there are several mathematical methods.

Method 1: detect remarkable solutions, like remarkable identities, it is sometimes easy to find the equation by analyzing the values (by comparing two successive values or by identifying certain precise values).

Example: a function has for points (couples $ (x,y) $) the coordinates: $ (1,2) (2,4), (3,6), (4,8) $, the ordinates increase by 2 while the abscissas increase by 1, the solution is trivial: $ f (x) = 2x $

Method 2: use a interpolation function, more complicated, this method requires the use of mathematical algorithms that can find polynomials passing through any points. The most well known interpolations are Lagrangian interpolation and Neville interpolation.

NB: for a given set of points there is an infinity of solutions because there are infinite functions passing through certain points. dCode tries to propose the most simplified solutions possible, based on affine function or polynomial of low degree (degree 2 or 3).

Source code

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