6.838, Computational Geometry; Fall 2001

Point Location

Sergi Elizalde & David Pritchard


Introduction / Motivation

Formalization of the Problem

Single Shot Algorithm

Naive Algorithm

Idea

Analysis

An Improved Algorithm

The Trapezoidal Map

Assumptions / Simplifications

Navigating the Map (1)

Navigating the Map (2)

Searching - Idea

An Incremental Randomized Algorithm

Global Description

Finding Intersected Trapezoids

Incrementing T and D - Simple Case

Incrementing T - General Case

Incrementing D - General Case

Analysis

Expected Performance

Proof: Query Time

Proof: Storage Size

Proof: Construction Time

Removing Our Assumptions

Symbolic Transformation

A Tail Estimate

A Tail Estimate (1)

A Tail Estimate (2)

Maximum Search Path Length

Linear Storage, Logarithmic Queries with n log n Construction Time

Related Problems