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;;; http://johnj.com/from-elegance-to-speed.html
;;;
;;; The author of the above blog post says that his `smt-8` was slow so he re-wrote it in
;;; Common Lisp and got nearly 300x improvement. I wrote some pure Clojure variations
;;; showing much improved performance over the original.
;;;
;;; Criterium for benchmarking: https://github.com/hugoduncan/criterium/
(ns miner.smt
(:require [criterium.core :as cc]))
@miner
miner / pal.clj
Created October 2, 2018 20:30
find longest palindromic substring using Clojure
(ns miner.pal
(:require [criterium.core :as crit]
[clojure.string :as str]))
;; An exercise from Apropos Clojure #18 video cast:
;; https://www.youtube.com/watch?v=elF9BPa0Np4
;;
;; Their solution is something like this...
@miner
miner / apropos3.clj
Created March 19, 2018 20:47
a stateful transducer inspired by @apropos_cast episode #3
(defn digits [n]
{:pre [(int? n) (>= n 0)]}
(loop [digs () remainder n]
(if (< remainder 10)
(conj digs remainder)
(recur (conj digs (rem remainder 10)) (quot remainder 10)))))
(defn digits+rev [n]
(let [ds (digits n)]
(concat ds (reverse ds))))
@miner
miner / map-alt.clj
Created March 14, 2018 19:28
map-alt transducer
;; map-alt is like the map xform but calls the funtions in an alternating order
;; (f i0) (g i1) (h i2) (f i3) ...
;;
;; In other words, map-alt spreads fn calls across elements, whereas (mapcat (juxt ...)) calls all
;; fns on each element.
(defn map-alt
([] (map identity))
([f] (map f))
@miner
miner / kein.sh
Last active January 4, 2021 09:35 — forked from cgrand/kein.sh
Launch a plain clojure repl according to project.clj without leiningen (most of the time)
#!/bin/bash
# launch a clojure plain repl but with options and classpath matching project.clj
# Except when project.clj changes (and on first launch), lein is not called.
if [ ! -f "project.clj" ]; then
echo "No project.clj"
exit 1
fi
# stat (mostly) protects against staleness of copied project dir
@miner
miner / bowling.clj
Last active January 4, 2021 09:35
Bowling Kata in Clojure
(ns miner.bowling)
;; http://codingdojo.org/cgi-bin/index.pl?KataBowling
;; https://www.javacodegeeks.com/2016/05/bowling-kata-clojure-f-scala.html
;; game is a string, encoding balls rolled
;; X for strike
;; / for spare
;; - for a miss or gutter ball
;; 1-9 for that many pins
@miner
miner / gdiff
Last active October 26, 2022 18:29
using FileMerge as git difftool on Mac OS X
#!/bin/bash
# my git difftool, calls FileMerge with project as -merge target
# better than using opendiff
#
# cd to your project dir and and run difftool like this:
# git difftool -d -x gdiff
# find top level of git project
dir=$PWD
until [ -e "$dir/.git" ]; do
(ns miner.dijkstra-primes)
;; ----------------------------------------------------------------------
;; http://heinrichhartmann.com/2016/04/03/Dijkstra's-Prime-Number-Algorithm.html
;; https://github.com/HeinrichHartmann/DijkstraPrimes/blob/master/Primes.lua
;; Converted to Clojure by SEM. Note that there are lots of shadowing and recursive calls in
;; the Clojure code to avoid the mutation in the original code. The Clojure loops are a bit
;; ugly. Not sure if this is the best way to do things. However, the performance is pretty
;; good.

Keybase proof

I hereby claim:

  • I am miner on github.
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  • I have a public key whose fingerprint is DB15 4E49 B5BD BE5A 10B4 4437 6A9B 8B0A 4D6A 8900

To claim this, I am signing this object:

(ns miner.lucky
(:require [clojure.data.avl :as avl]))
;; http://en.wikipedia.org/wiki/Lucky_number
(defn lucky-avl
([max] (lucky-avl 1 (apply avl/sorted-set (range 1 max 2))))
([i avl]
(let [n (nth avl i nil)]
(if (and n (<= n (count avl)))