+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)) == dd. Used to solve linear systems.
+ ##
+
+ coefficients = [];
+
+ for xj = xs
+ this_coeff = 1;
+ for xi = xs
+ if (xi != xj)
+ ## Append (xj - xi) to the vector of coefficients.
+ this_coeff = this_coeff * (1 / (xj - xi));
+ end
+ end
+ coefficients(end+1) = this_coeff;
+ end
+end