function coefficients = divided_difference_coefficients(xs) % Compute divided difference coefficients of `f` at points `xs`. % % INPUTS: % % * ``xs`` - A vector containing x-coordinates. % % OUTPUTS: % % * ``coefficients`` - The vector of coefficients such that % dot(coefficients, f(xs)) == f[xs]. Used to solve linear systems. % coefficients = []; for xj = xs this_coeff = 1; for xi = xs if (xi != xj) this_coeff = this_coeff * (1 / (xj - xi)); end end coefficients(end+1) = this_coeff; end end