Chee-keng Yap

Publication List Details

Period

1988 - 2008

Number

20

Co-Authors

Complete Numerical Isolation of Real Zeros in General Triangular Systems ∗ (2008)

Jin-san Cheng, Xiao-shan Gao, Chee-keng Yap

Abstract. We consider the computational problem of isolating all the real zeros of a zero-dimensional triangular polynomial system Fn ⊆ Z[x1,...,xn]. We present a complete numerical algorithm for...

Towards Exact Geometric Computation (To Appear, Computational Geometry: Theory and Applications) (2007)

Chee-keng Yap

Exact computation is assumed in most algorithms in computational geometry. In practice, implementors perform computation in some fixedprecision model, usually the machine floating-point arithmetic....

Combinatorial Complexity of Signed Discs (2007)

Diane L. Souvaine, Chee-keng Yap

Let C + and C \Gamma be two collections of topological discs of arbitrary radii. The collection of discs is `topological' in the sense that their boundaries are Jordan curves and each pair of...

. Our algorithm runs in O((n + f)log (2007)

Timothy M. Chan, Jack Snoeyink, Chee-keng Yap

In this paper, we give an algorithm for output-sensitive construction of an f-face convex hull of a set of n points in general position in E 4

Primal Dividing and Dual Pruning: Output-Sensitive Construction of 4-d Polytopes and 3-d Voronoi Diagrams (1997)

Timothy M. Chan, Jack Snoeyink, Chee-keng Yap

In this paper, we give an algorithm for output-sensitive construction of an f-face convex hull of a set of n points in general position in E 4 . Our algorithm runs in O((n + f)log 2 f) time and uses...

Admissible Orderings and Bounds for Gröbner Basis Normal Form Algorithms (1997)

T. Dubé, B. Mishra, Chee-keng Yap

The concepts of admissible orderings and normal form algorithm are basic in Buchberger's Gröbner basis algorithm. We present a constructive and elementary proof of Robbiano's...

Precision-Sensitive Euclidean Shortest Path in 3-Space (1995)

Jürgen Sellen, Joonsoo Choi, Chee-keng Yap

This paper introduces the concept of precision-sensitive algorithms, in analogy to the well-known output-sensitive algorithms. We exploit this idea in studying the complexity of the 3-dimensional...

Rectilinear Geodesics in 3-Space (Extended Abstract) (1995)

J. Choi, Joonsoo Choi, Chee-keng Yap

) Joonsoo Choi Chee-Keng Yap Courant Institute of Mathematical Sciences New York University 251, Mercer Street New York, NY 10012 Abstract Let B be any finite set of pairwise-disjoint, axes-parallel...

Approximate Euclidean Shortest Paths In 3-Space (1994)

Joonsoo Choi, Jürgen Sellen, Chee-keng Yap

Papadimitriou's approximation approach to the Euclidean shortest path (ESP) in 3space is revisited. As this problem is NP-hard, his approach represents an important step towards practical...

Approximate Euclidean Shortest Path in 3-Space (1994)

Joonsoo Choi, Jürgen Sellen, Chee-keng Yap

Papadimitriou's approximation approach to the Euclidean shortest path (ESP) in 3-space is revisited. As this problem is NP-hard, his approach represents an important step towards practical...

A Basis for Implementing Exact Geometric Algorithms (Extended Abstract) (1993)

Thomas Dube, Chee-keng Yap

) Thomas Dub'e The College of the Holy Cross Worcester, Massachusetts Chee-Keng Yap y Courant Institute, NYU New York, New York October 15, 1993 Abstract Our ultimate goal is to develop exact...

The Geometry in Constraint Logic Programs (1993)

Thomas Dube, Chee-keng Yap

Many applications of constraint programming languages concern geometric domains. We propose incorporating strong algorithmic techniques from the study of geometric and algebraic algorithms into the...

Combinatorial Complexity of Translating a Box in Polyhedral 3-Space (1993)

Dan Halperin, Chee-keng Yap

We study the space of free translations of a box amidst polyhedral obstacles with n vertices. We show that the combinatorial complexity of this space is O(n 2 ff(n)) where ff(n) is the inverse...

Refinement Methods for Geometric Bounds in Constructive Solid Geometry (1991)

Stephen Cameron, Chee-keng Yap

In Constructive Solid Geometry, geometric solids are represented as trees whose leaves are labelled by primitive solids and whose internal nodes are labelled by set-theoretic operations. A bounding...