Shen / Qi

A collection of 10 posts

Functional Programming

Corporate funding for Shen

It looks like it might be coming sooner than I thought. I’m sure Shenturions everywhere will find this news incredibly exciting for the future of Shen. I can’t wait to see how things progress.  
Clojure

Purely Functional Data Structures & Algorithms : Selection Sort

*Updated @ 2012-08-31 02:08:58 due to internet pedantry* Previously, previously. According to Wikipedia : InΒ computer science, aΒ Selection sortΒ is aΒ sorting algorithm, specifically anΒ in-placeΒ comparison sort. It hasΒ O(n2) time complexity, making it inefficient on large lists, and generally performs
Functional Programming

Purely Functional Data Structures & Algorithms : Union-Find

It’s been a while since I last posted in this series. Today we look at the disjoint-set data structure, specifically disjoint-set forestsΒ and the complementary algorithm : union-find. InΒ computing, aΒ disjoint-set data structureΒ is aΒ data structureΒ that keeps track of a
Functional Programming

Quick Sort in Shen

A Shen type-checked implementation of Quick Sort is even more elegant/terse compared with the CL version posted previously. Pattern-matching and currying make this possible. (tc +) (define filter {(A --> boolean) --> (list A) --> (list A)} _ [] -> [] T? [A
Clojure

Happy Pi Day in Shen

Here’s a port of the previous Qi II code to Shen. Run with Hakan Raberg’s 0.1.4 version of shen.clj (Shen implemented in Clojure !). * Accurately calculates N digits of Pi using Machin's formula with fixed point arithmetic and
Clojure

Shen/Kl arrive

The first publicly available version of Shen/Kl has been released. The Shen mission is to develop an ultra-portable version of Qi that can run under a wide variety of platforms and which incorporates missing features in Qi such as streams. The targeted platforms
Functional Programming

Purely Functional Data Structures & Algorithms : Fast Fourier Transform in Qi

In this second post in this series we look at an implementation of the always useful Fast Fourier Transform. (FFT) An algorithm for computing the Fourier transform of a set of discrete data values. Given a finite set of data points, for example a
Functional Programming

Purely Functional Data Structures & Algorithms : Red-Black Trees in Qi

Update 2011/06/28 : Source has been modified to compile with Shen This is the first in a series of posts that will demonstrate the implementation of many well-known(and less known) data structures and algorithms using a purely functional approach. We will use
Clojure

Happy PI day ! (in QiII)

Qi is the future of Lisp. It is Lisp with many great features such as pattern-matching, a turing complete static type system (even more powerful than Haskell’s type system) and many others. So in the spirit of PI day, here’s
Functional Programming

Summer 2010 reading

“Let over Lambda – 50 Years of Lisp” by Doug Hoyte This one had been sitting on my bookshelf for almost a year. “Let Over Lambda is one of the most hardcore computer programming books out there. Starting with the fundamentals,