bortels

-- Lua 5.1+ base64 v3.0 (c) 2009 by Alex Kloss <alexthkloss@web.de>
-- licensed under the terms of the LGPL2

-- character table string
local b='ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'

-- encoding
function enc(data)
    return ((data:gsub('.', function(x) 
        local r,b='',x:byte()

hellerbarde

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

asmeurer

hmartiro

ZeroMQ vs Redis

This document is research for the selection of a communication platform for robot-net.

Goal

The purpose of this component is to enable rapid, reliable, and elegant communication between the various nodes of the network, including controllers, sensors, and actuators (robot drivers). It will act as the core of robot-net to create a standardized infrastructure for robot control.

Requirements:

jiffyclub

#!/usr/bin/env python
"""
Prepare an HTML file from SnakeViz for use as a static page.
This makes it so all static files are loaded from a CDN instead
of from the local server.

To get the SnakeViz HTML file run the snakeviz CLI to load a profile
in your browser, than save that page as an HTML file to your computer.

Finally, run this script on that HTML file.

navin-mohan

#!/bin/bash
# Script to harden ssh on ubuntu/debian server
# follow on my blog http://www.coderew.com/hardening_ssh_on_remote_ubuntu_debian_server/ 
# checkout the repo for more scripts https://github.com/nvnmo/handy-scripts

read -p "Enter your server IP:" serverIP # prompt for server IP
read -p "Enter your username(requires root privileges):" username # prompt for username
printf "\nChanging the default SSH port is one of the easiest\n things you can do to help harden you servers security. \nIt will protect you from robots that are programmed \nto scan for port 22 openings, and commence \ntheir attack."
printf "\n"
read -p "Do you want to change default SSH port?[Y/n]" -n 1 portChange

lokhman

WARNING

May contain out of date information. Check the comments below!

The list of actions listed below was taken mostly from Book Of Zeus with minor modifications and did the job well for Ubuntu version, which was available at that moment (May 2016). This gist was created for internal use and was never meant to be discovered by the web, although Google managed to find and index this page, which was a great surprise for me. Please check the original source for the updated information (links are provided in most of the sections), and read the comments below: they provide more details about the usage experience.

System Updates

http://bookofzeus.com/harden-ubuntu/initial-setup/system-updates/

Keeping the system updated is vital before starting anything on your system. This will prevent people to use known vulnerabilities to enter in your system.

farrajota

--[[
    Create a binary tree using two ways: NN containers and nn.gModule containers. 
    This example is fairly simple, and the default fully-connected layers are all
    of size 100. However, this should also be simple to modify to allow different 
    fc layers with varying inputs/outputs if desired (for example: input a table
    storing input+output configuration values for each of the sub-branch's level).
]]

require 'nn'
require 'nngraph'

cburgdorf

import numpy as np
from keras.models import Sequential
from keras.layers.core import Activation, Dense

training_data = np.array([[0,0],[0,1],[1,0],[1,1]], "float32")
target_data = np.array([[0],[1],[1],[0]], "float32")

model = Sequential()
model.add(Dense(32, input_dim=2, activation='relu'))
model.add(Dense(1, activation='sigmoid'))

Egor-Skriptunoff

__=2;print(1/(

        -  ~  -  ~  -  ~  -  ~  -  ~  -  ~  -  ~  -
       ~ __/ ~  -  ~  -  ~  -  ~  -  ~  -  ~  -  ~
      - __/ -  ~  - __/ -  ~ __/ ~  - __/__/ ~  -
     ~ __/ ~  -  ~ __/ ~  - __/ -  ~  -  ~ __/ ~
    - __/ -  ~  - __/ -  ~ __/ ~  - __/__/__/ -
   ~ __/ ~  -  ~ __/ ~  - __/ - __/ -  ~ __/ ~
  - __/__/__/__/ ~ __/__/__/ ~  - __/__/__/ -
 ~  -  ~  -  ~  -  ~  -  ~  -  ~  -  ~  -  ~