themattchan

import edu.princeton.cs.algs4.*;
import java.util.*;

public class KdTree {
	private abstract class Node implements TreeApply {
		protected Point2D point;
		public abstract void apply (TreeFunction function);
	}

	private interface TreeFunction {

themattchan

# -*- mode: snippet; require-final-newline: nil -*-
# name: homework-sty
# key: homework
# binding: direct-keybinding
# --
\documentclass[10pt,letterpaper]{article}
\usepackage[T1]{fontenc}
\usepackage[parfill]{parskip} % line break instead of indentation
\usepackage[margin=1in]{geometry}
\usepackage{float}  % use attribute [H] to force images to stay where they should be

themattchan

%
% Listings hacks to emulate the math-style Haskell from Functional Pearls,
% Programming in Haskell, Pearls of Functional Algorithm Design. and other books.
%
% This is probably as close an emulation of the math-style generated with lhs2tex as I can get.
%
% Modified from:
%   https://raw.githubusercontent.com/UCSD-PL/230-web/master/templates/haskellListings.tex
%

themattchan

(* Folds *)
let rec fold_right f a xs = match xs with
  | [] -> a
  | x :: xs -> f (fold_right f a xs)  x

let rec fold_left f a xs = match xs with
  | [] -> a
  | x :: xs -> fold_left f (f a x) xs

(*  TODO: implement monoids and the foldable typeclass with modules*)

themattchan

{- LANGUAGE  TupleSections -}
import Control.Monad
import qualified Data.Set as S

--type State  = String
type Symbol = Char
data DFA st = DFA { states   :: [st],
                    alphabet :: [Symbol],
                    delta    :: st -> Symbol -> st,
                    startSt  :: st

themattchan

#lang racket
(require xml)
(require xml/xexpr)


(define to-html (compose display
                         xexpr->string))

(define CONFIGS '((siteName "Andromeda")
                  (latitude 1234.567)

themattchan

#lang racket
(require test-engine/racket-tests)


(define (rotations lst)
  (letrec ((go (λ (n acc)
    (if (= n 0) acc
        (go (sub1 n) (let ((c (car acc)))
                       `(,`(,@(cdr c) ,(car c)) ,@acc)))))))
  (reverse (go (length lst) (list lst)))))

themattchan

#lang racket

#|

Simplified SXML grammar

<Element>    ::= (<Symbol> <Children>...)
              |  (<Symbol> <AttribList> <Children>...)
<Children>   ::= <Element> | <Value>
<AttribList> ::= (<Attribute> ...) | (@ <Attribute> ...)

themattchan

module Golf where
import Data.List

skips :: [a] -> [[a]]
skips xs = map (map snd) $ zipWith filter filters (replicate len ids)
  where len     = length xs
        ids     = zip [1..len] xs
        filters = map (\n (a,_) -> a `mod` n == 0) [1..len]

localMaxima :: [Integer] -> [Integer]

themattchan

# MarkdownBlock
# Insert & parse Markdown anywhere, even nested in html
#
# Author: Matthew Chan <matt@themattchan.com>
# Date: January 2015
# License: GNU GPL
#
# Usage:
# {% markdown %} 
# <md_text>