Salvatore Sanfilippo antirez

Computer programmer based in Sicily, Italy. I mostly write OSS software. Born 1977. Not a puritan.

antirez / huffmancode.rb

Created April 2, 2009 22:48

recursive huffman coding

	def buildHuffmanCode(ftab)
	if ftab.length == 1
	ftab
	else
	ftab = ftab.sort {\|a,b\| a[0] <=> b[0]}
	left = ftab[0]
	right = ftab[1]
	freq = left[0]+right[0]
	left = left[1].map{\|x\| x.merge({:code => "0"+x[:code]})}
	right = right[1].map{\|x\| x.merge({:code => "1"+x[:code]})}

antirez / gist:120067

Created May 29, 2009 17:05

	# Build an inverted index for a full-text search engine with Redis.
	# Copyright (C) 2009 Salvatore Sanfilippo. Under the BSD License.
	# USAGE:
	#
	# ruby invertedindex.rb add somedir/*.c
	# ruby invertedindex.rb add somedir/*.txt
	# ruby search your query string

	require 'rubygems'
	require 'redis'

antirez / gist:259466

Created December 18, 2009 12:24

	#!/bin/sh

	PIDFILE=/var/run/redis_6379.pid
	EXEC=/usr/local/bin/redis-server
	CONF="/etc/redis/6379.conf"
	REDISPORT=6379

	case "$1" in
	start)
	if [ -f $PIDFILE ]

antirez / Redis interactive memory usage changes reporting script.rb

Created January 4, 2010 18:52

antirez / gist:277164

Created January 14, 2010 13:33

	% ssh -v -i ~/.ssh/DinamicheRosaKeyPair.pem [email protected]
	OpenSSH_5.2p1, OpenSSL 0.9.8k 25 Mar 2009
	debug1: Reading configuration data /etc/ssh_config
	debug1: Connecting to 79.125.10.167 [79.125.10.167] port 22.
	debug1: Connection established.
	debug1: identity file /Users/antirez/.ssh/DinamicheRosaKeyPair.pem type -1
	debug1: Remote protocol version 2.0, remote software version OpenSSH_5.1p1 Debian-5ubuntu1
	debug1: match: OpenSSH_5.1p1 Debian-5ubuntu1 pat OpenSSH*
	debug1: Enabling compatibility mode for protocol 2.0
	debug1: Local version string SSH-2.0-OpenSSH_5.2

antirez / gist:277334

Created January 14, 2010 17:32

antirez / gist:280994

Created January 19, 2010 15:24

	# Power law (log tail) distribution
	# Copyright(C) 2010 Salvatore Sanfilippo
	# this code is under the public domain

	# min and max are both inclusive
	# n is the distribution power: the higher, the more biased
	def powerlaw(min,max,n)
	max += 1
	pl = ((max(n+1) - min(n+1))rand() + min(n+1))*(1.0/(n+1))
	(max-1-pl.to_i)+min

antirez / gist:283192

Created January 21, 2010 21:03

	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include <limits.h>
	#include <math.h>

	unsigned long longtailprng(unsigned long min, unsigned long max, int n) {
	unsigned long pl;
	double r = (double)(random()&(INT_MAX-1))/INT_MAX;

antirez / gist:283372

Created January 22, 2010 00:39

	Usage: redis-load ... options ...

	host <hostname> Server hostname (default 127.0.0.1)
	port <hostname> Server port (default 6379)
	clients <clients> Number of parallel connections (default 50)
	requests <requests> Total number of requests (default 10k)
	writes <percentage> Percentage of writes (default 50, that is 50%)
	mindatasize <size> Min data size of SET values in bytes (default 1)
	maxdatasize <size> Min data size of SET values in bytes (default 64)
	datasize <size> Set both min and max datasize to the same value

antirez / gist:283886

Created January 22, 2010 16:31