Algorithms and Data Structures for External Memory

8.1 Distribution Sweep 71
Goodrich et al. [179], Zhu [364], Arge et al. [57], Arge et al. [48],
and Crauser et al. [122, 123] develop EM algorithms for those batched
problems using the following EM paradigms:
Distribution sweeping, a generalization of the distribution paradigm of
Section 5.1 for “externalizing” plane sweep algorithms.
Persistent B-trees, an offline method for constructing an optimalspace
persistent version of the B-tree data structure (see Section
11.1), yielding a factor of B improvement over the generic
persistence techniques of Driscoll et al. [142].
Batched filtering, a general method for performing simultaneous EM
searches in data structures that can be modeled as planar layered
directed acyclic graphs; it is useful for 3-D convex hulls
and batched point location. Multisearch on parallel computers
is considered in [141].
External fractional cascading, an EM analogue to fractional cascading
on a segment tree, in which the degree of the segment tree is
O(m α ) for some constant 0