def eval_fitness(self, chromosome):
coefficients = self.translator.translate_chromosome(chromosome)<EOL>solution_y = self.compute_y(coefficients, self.num_x)<EOL>fitness = -<NUM_LIT:1> * self.compute_err(solution_y, coefficients)<EOL>return fitness<EOL>
Evaluate the polynomial equation using coefficients represented by a
solution/chromosome, returning its error as the solution's fitness.

return:  fitness value