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@tbuktu
tbuktu / BigInteger.java.phase3
Created January 7, 2012 20:58
Patched BigInteger using efficient algorithms for multiplication and division
/*
* Copyright (c) 1996, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
@eed3si9n
eed3si9n / kind.scala
Created September 3, 2012 16:40
calculates a type's kind
// requires Scala 2.10.0-M7
def kind[A: scala.reflect.TypeTag]: String = {
import scala.reflect.runtime.universe._
def typeKind(sig: Type): String = sig match {
case PolyType(params, resultType) =>
(params map { p =>
typeKind(p.typeSignature) match {
case "*" => "*"
case s => "(" + s + ")"
}
@robinsloan
robinsloan / langoliers.rb
Last active April 7, 2024 13:22
The Langoliers, a tweet deletion script
require "rubygems"
require "twitter"
require "json"
# things you must configure
TWITTER_USER = "your_username"
MAX_AGE_IN_DAYS = 1 # anything older than this is deleted
# get these from dev.twitter.com
CONSUMER_KEY = "your_consumer_key"
@johnynek
johnynek / hdfsio.scala
Created August 25, 2013 05:34
IO Monad for the HDFS FileSystem: http://hadoop.apache.org/docs/r1.0.4/api/org/apache/hadoop/fs/FileSystem.html Make your HdfsIO[T] object (for example op), set an implicit FileSystem, then call HdfsIO.run(op) TOTALLY UNTESTED! (but it does compile)
import java.io.{FileNotFoundException, IOException}
import org.apache.hadoop.fs.{
FileSystem,
FileStatus,
FSDataInputStream,
FSDataOutputStream,
Path
}
@johnynek
johnynek / gist:8961994
Last active August 29, 2015 13:56
Some Questions with Sketch Monoids

Unifying Sketch Monoids

As I discussed in Algebra for Analytics, many sketch monoids, such as Bloom filters, HyperLogLog, and Count-min sketch, can be described as a hashing (projection) of items into a sparse space, then using two different commutative monoids to read and write respectively. Finally, the read monoids always have the property that (a + b) <= a, b and the write monoids has the property that (a + b) >= a, b.

##Some questions:

  1. Note how similar CMS and Bloom filters are. The difference: bloom hashes k times onto the same space, CMS hashes k times onto a k orthogonal subspaces. Why the difference? Imagine a fixed space bloom that hashes onto k orthogonal spaces, or an overlapping CMS that hashes onto k * m length space. How do the error asymptotics change?
  2. CMS has many query modes (dot product, etc...) can those generalize to other sketchs (HLL, Bloom)?
  3. What other sketch or non-sketch algorithms can be expressed in this dual mo
anonymous
anonymous / private_deps.md
Created June 12, 2015 19:07
Better Dependency Hygiene With Private Dependencies On JVM

Better Dependency Hygiene With Private Dependencies On JVM

A common pain when working with large projects is the diamond dependency. Consider a commonly used library such as ASM. One wants to build a big application reusing many powerful libraries, but unfortunately many of my desired dependencies themselves depend on different and incompatible versions of ASM. While compiling my code, since ASM does not appear in any APIs I touch, everything compiles fine, but at runtime the JVM only includes one version of classes of a given name leading to runtime binary errors.

OSGI Bundles are related to solving this problem, but it appears that is a heavy solution that has proven to be too cumbersome to actually use. Here we propose a lighter weight approach that benefits each incremental project that adopts this method.

Private dependencies are implemented by a build tool plug-in. In the build where one declares dependencies, one can label a jar dependency to be a private dependency. A private dependency means tha

@sooryan
sooryan / blake2.md
Last active March 12, 2024 02:37
A quick summary of blake2, a cryptographic hash function

BLAKE2

  • BLAKE2 is an improved version of the SHA-3 finalist BLAKE, and was designed by a team of experts in cryptanalysis, implementation, and cryptographic engineering; namely Jean-Philippe Aumasson, Samuel Neves, Zooko Wilcox-O'Hearn and Christian Winnerlein.

  • BLAKE2s (the one checksum currently uses) computes a message digest that is 256 bits long, and represented as a 64-character hexadecimal number, e.g. 4264cb256d94533b6e152da59256638bc6adfda3efc5550d7607d4e6e45592fc.

Types

  • BLAKE2b (or just BLAKE2) is optimized for 64-bit platforms and produces digests of any size between 1 and 64 bytes.
@fnky
fnky / ANSI.md
Last active June 14, 2024 06:14
ANSI Escape Codes

ANSI Escape Sequences

Standard escape codes are prefixed with Escape:

  • Ctrl-Key: ^[
  • Octal: \033
  • Unicode: \u001b
  • Hexadecimal: \x1B
  • Decimal: 27
@Gabriella439
Gabriella439 / trans.md
Last active November 28, 2023 06:30
I'm trans

I'm writing this post to publicly come out as trans (specifically: I wish to transition to become a woman).

This post won't be as polished or edited as my usual posts, because that's kind of the point: I'm tired of having to edit myself to make myself acceptable to others.

I'm a bit scared to let people know that I'm trans, especially because I'm not yet in a position where I can transition (for reasons I don't want to share, at least not in public) and it's really shameful. However, I'm getting really