Blog

Determining List Steepness in a Homomorphism

July 10, 2009
A list of numbers is called steep if each element is larger than the sum of elements to its right. It is an example we often use when we talk about tupling. Can we determine the steepness of a list by a list homomorphism? ... [8 comments...].

The Windowing Technique for Longest Segment Problems

June 20, 2009
Reviewing Zantema’s “windowing” technique for computing the longest segment of the input that satisfies a suffix-closed predicate. ... [no comments...].

Longest Segment Satisfying Suffix and Overlap-Closed Predicates

June 7, 2009
Translating Zantema’s work to Bird-Meertens style, to compute the longest consecutive segment of the input that satisfies a predicate that is suffix and overlap-closed. ... [no comments...].

On a Basic Property for the Longest Prefix Problem

June 2, 2009
Giving a constructive proof for one of the essential properties in Hans Zantema’s Longest Segment Problems. ... [no comments...].

Beamer Article Mode Does Not Save Paper?

May 19, 2009
Among all the features of Beamer I like is the article mode with which I can produce handouts. “It’s easier to read, and it saves paper!” I thought. ... [no comments...].

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Software

  • AoPA — Algebra of Programming in Agda: The AoPA library allows one to encode Algebra of Programming style program derivation, both functional and relational, in Agda, accompanying the paper Algebra of Programming Using Dependent Types (MPC 2008) developed in co-operation with Hsiang-Shang Ko and Patrik Jansson.
  • Push: Improving Heap Residency for Lazy Stream Processing by Concurrency: Prototype implementation of a language Push, accompanying our recently submitted paper. The prototype is implemented and prepared by Ta-Chung Tsai.While studying XML stream processing, we noticed that programmers need concurrency to save space, especially in a lazy language. We propose the idea of pushing datatypes — when a pushing closure is demanded, all expressions referring
  • Maximum Segment Sum and Density with Bounded Lengths: It may be surprising that variations of the maximum segment sum (MSS) problem, a textbook example for the squiggolists, are still active topics for algorithm designers. These literate Haskell scripts presents a program solving two recently studied variations: computing the maximum sum of segments not longer than an upper-bound, and the maximum density (average) of
  • Countdown: Programs and profiling results accompanying the paper Countdown: a case study in origami programming. [GZipped Tarball]
  • Inv: The injective language Inv, together with the language X, the XEditor, and the HaXml embedding. [GZipped Tarball]

Academic Activities

Colleagues

Research assistants: Previous research assistants: