fact: Definition weighted_sum (p1 p2 : pt) (weight1 : Q) := Bpt (p_x p1 * weight1 + p_x p2 * (1 - weight1)) (p_y p1 * weight1 + p_y p2 * (1 - weight1)).
imports: mathcomp(all_ssreflect) ZArith QArith List String OrderedType OrderedTypeEx FMapAVL