nodelagrange
Implements Lagrange polynomial interpolation for both the numbers you are used to as well as finite fields. Given a list of x values and a list of y values, it will attempt to solve f(x) for a given x value.
All finite field arithmetic uses the
galois NPM module (npm show galois
).
Functions

base10(x, xValues, yValues)
 Assumes the standard decimal system. 
galois(x, xValues, yValues, gfW)
 ThegfW
parameter is passed to thegalois
module functions, which uses it as the exponent to define the field size (2^w
). 
splitCoords(coords)
 The above math functions take two separate arrays, one for x values and one for y values, but your application is likely to use an array of tuples to define coordinates. This utility function splits them out, giving you a tuple of x and y values ([xValues, yValues]
).
Examples
See ./tests/lagrange.js
for examples using different equations.