malcolmgreaves

from functools import partial
from operator import concat
from os.path import isfile

from fold import foldl


def _list_files_from(part, prev):
    current = "%s/%s" % (prev, part)
    if isfile(current):

malcolmgreaves

UNDERSTANDING HASH FUNCTIONS
by Geoff Pike

Version 0.2 --- early draft --- comments and questions welcome!
References appear in square brackets.

1 INTRODUCTION

Hashing has proven tremendously useful in constructing various fast
data structures and algorithms.  It is typically possible to simplify

mcg1969

machine:
  environment:
    MINICONDA: "$HOME/miniconda"
    MINICONDA_PATH: "$MINICONDA/bin"
    PATH: "$MINICONDA_PATH:$PATH"
    CONDA: "$MINICONDA_PATH/conda"
    ANACONDA: "$MINICONDA_PATH/anaconda"
    # This ensures we don't accidentally pull in ~/.condarc
    # if it happens to be there for some strange reason
    CONDARC: "$MINICONDA/condarc.none"

aparrish

mkolod

#include <cmath>
#include <iostream>

using std::cout;
using std::endl;

float quake3_hack(float number) {
  float x2 = number * 0.5f;
  float y  = number;
  long i  = *(long*) & y;

yossorion

What I Wish I'd Known About Equity Before Joining A Unicorn

Disclaimer: This piece is written anonymously. The names of a few particular companies are mentioned, but as common examples only.

This is a short write-up on things that I wish I'd known and considered before joining a private company (aka startup, aka unicorn in some cases). I'm not trying to make the case that you should never join a private company, but the power imbalance between founder and employee is extreme, and that potential candidates would

malcolmgreaves

object BinomialHypothesisTest {
  
  def tTestBinomial(p1:Double, n1:Int, p2:Double, n2:Int): TtestRes = {
    val k =  (n1*p1 + n2*p2) / (n1 + n2).toDouble
    val z = (p1 - p2) / math.sqrt( k*(1 - k) * (1 / n1.toDouble + 1 / n2.toDouble) )
    if(z > scoreForTwoTailed95CiPval)
      RejectNull
    else
      FailToReject
  }

ebautistabar

Recovering deleted files in Ubuntu with ext4 filesystem

Recently, I deleted some files by mistake in a Ubuntu machine with an ext4 fs. These notes document the steps I took to get them back.

Important

• this procedure assumes that the partition that contained the deleted files is different from the root partition, as that was the scenario with which I had to deal (deleted files were in my home dir). The procedure needs that the partition that contained the files is unmounted, so if the deleted files were in the root partition, the process would be a bit different (e.g. storing the fs journal in a USB stick, using a live CD/USB to boot and issue the commands, etc.)
• if something is not clear, you need more information, etc. check the sources below

With that out the way, let's begin.

bastman

Docker - How to cleanup (unused) resources

Once in a while, you may need to cleanup resources (containers, volumes, images, networks) ...

delete volumes

// see: https://github.com/chadoe/docker-cleanup-volumes

$ docker volume rm $(docker volume ls -qf dangling=true)

$ docker volume ls -qf dangling=true | xargs -r docker volume rm

mkolod

object DiffieHellmanMerkle {

  import java.math.BigInteger
  import scala.language.implicitConversions
  import scala.util.Random

  def main(args: Array[String]): Unit =
    println(
      diffieHellmanMerkle(generator = 3, modulus = 17, alicePrivateKey = 54, bobPrivateKey = 24)
    )