Scaling and related techniques for geometry problems

Abstract
Three techniques in computational geometry are explored: Scaling solves a problem by viewing it at increasing levels of numerical precision; activation is a restricted type of update operation, useful in sweep algorithms; the Cartesian tree is a data structure for problems involving maximums and minimums. These techniques solve the minimum spanning tree problem in Rk1 and Rk@@@@ in O(n(lg n)rlg lg n) time and O(n) space, where for Rk@@@@ and k ≥ 3, r &equil; k−2; for Rk1, r &equil; 1, 2, 4 for k &equil; 3, 4, 5 and r &equil; k for k 5. Other problems solved include Rk1and Rk all nearest neighbors, post office and maximum spanning tree; Rk maxima, Rk rectangle searching problems, and Zkp all nearest neighbors (1 ≤ p ≤ @@@@).