Installing Docker on an Ubuntu AWS EC2 machine

sudo apt-get update

# Install packages to allow apt to use a repository over HTTPS:
sudo apt-get install \
    apt-transport-https \
    ca-certificates \
    curl \
    software-properties-common

# For "sudo: unable to resolve host ip-x-x-x-x" errors, follow the following link to set "DNS Hostnames" to True:
# http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/vpc-dns.html#vpc-dns-updating
sudo true

# Add Docker’s official GPG key
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -

# Verify that the key fingerprint is 9DC8 5822 9FC7 DD38 854A E2D8 8D81 803C 0EBF CD88.
sudo apt-key fingerprint 0EBFCD88

# Use the following command to set up the stable repository.
sudo add-apt-repository \
   "deb [arch=amd64] https://download.docker.com/linux/ubuntu \
   $(lsb_release -cs) \
   stable"

# Install the latest version of Docker CE
sudo apt-get update
sudo apt-get install docker-ce
sudo docker run hello-world

# Ref: https://docs.docker.com/engine/installation/linux/docker-ce/ubuntu/#install-using-the-repository

Set up RVM, Ruby, Gem & Jykll to serve a username.github.io blog

Here are the steps I took to set up RVM, Ruby, Gem & Jykll to serve a username.github.io blog on OSX:

# Install RVM (Ruby version manager) 
# Also read: http://rvm.io/rvm/install and check the script before running
curl -sSL https://get.rvm.io | bash -s stable --ruby

# Install Ruby (replace x.y.z with latest stable version of ruby)
rvm install x.y.z
rvm docs generate-ri
rvm use x.y.z --default

# Check other requirements are available for jekyll and install if missing
gem --version
gcc --version
make --version

# Install jekyll
gem install jekyll

# Install bundler and get all dependencies
gem install bundler
bundle install

# Clone an existing jekyll template, this one from BlackrockDigital is nice
git clone https://github.com/BlackrockDigital/startbootstrap-clean-blog-jekyll.git
cd startbootstrap-clean-blog-jekyll
bundle exec jekyll serve

# Periodically update Jekyll to match the GitHub Pages server
bundle update github-pages

Reference:
https://help.github.com/articles/setting-up-your-github-pages-site-locally-with-jekyll/
http://jekyllrb.com/docs/installation/
https://jekyllrb.com/docs/posts/
https://github.com/planetjekyll/awesome-jekyll-editors

Running PaCAL on OSX with conda

PaCAL is a great library for performing arithmetic on probabilistic random variables just like you do with ordinary program variables. Here is a more detailed paper on PaCAL.

There are a couple of gotchas setting it up on OSX with conda:

• Requires Python 2.7.x (3.x not supported as of March 2017)
• Required dependencies: numpy matplotlib sympy scipy
• Workaround for "RuntimeError: Python is not installed as a framework. The Mac OS X backend will not be able to function correctly if Python is not installed as a framework".

Here are the steps to set up PaCAL under a conda environment on OSX:

$ conda create -n pacal python=2.7
$ source activate pacal

(pacal) $ pip install numpy matplotlib sympy scipy
(pacal) $ pip install pacal

(pacal) $ python
Python 2.7.13 |Continuum Analytics, Inc.| (default, Dec 20 2016, 23:05:08)
[GCC 4.2.1 Compatible Apple LLVM 6.0 (clang-600.0.57)] on darwin
>>>
>>> # This TkAgg bit is to prevent the OSX 'Python is not installed as a framework' error.
>>> import matplotlib as mpl
>>> mpl.use('TkAgg')
>>>
>>> from pacal import *
Compiled interpolation routine not available
Compiled sparse grid routine not available
>>> dL = UniformDistr(1,3)
>>> L0 = UniformDistr(9,11)
>>> dT = NormalDistr(1,1)
>>> K = dL / (L0 * dT)
>>> K.plot()
>>> show()

Conda create environment commands

Conda create environment commands - super easy but nice to have as a reference:

# Python 2.7 $ conda create -n myenvname python=2.7 # Python 3.4 $ conda create -n myenvname python=3.4 # Python 3.x latest $ conda create -n myenvname python=3

$ source activate myenvname

More info: https://conda.io/docs/using/envs.html

If you then have a requirements.txt file, you can install the listed packages with:
conda install --yes --file requirements.txt

If you want to reproduce an existing conda environment on another machine, you can get a snapshot with:
conda env export > freeze.yml

which can then be restored via:
conda env create -f freeze.yml

Install xgboost on OSX with full OpenMP support in an anaconda virtualenv

The default gcc with OSX doesn't support OpenMP which enables xgboost to utilise multiple cores when training.

These steps show how to install gcc-6 with OpenMP support and build xgboost to support multiple cores and contain the python setup in an Anaconda virtualenv.

Install/update brew to support installing gcc-6:
See http://brew.sh/

Install gcc-6 with OpenMP support:
brew install gcc --without-multilib
Run brew doctor to ensure gcc-6 and g++-6 are linked correctly

Get latest xgboost from github:
git clone --recursive https://github.com/dmlc/xgboost

Build xgboost with gcc-6:
See https://xgboost.readthedocs.io/en/latest/build.html
cd xgboost; cp make/config.mk ./config.mk;
Ensure that the newly installed gcc-6 compliers are correct in config.mk (e.g. export CC = gcc-6; export CXX = g++-6)
make -j4
(This can take around 30 mins to build)

Create anaconda xgboost virtualenv:
conda create -n xgboost python=3.5
source activate xgboost

Install prerequisite numpy package in xgboost env:
conda install numpy

Set up xgboost for python xgboost virtualenv without sudo:
Ensure you are in the xgboost virtualenv (e.g. which python -> /Users/<user>/anaconda/envs/xgboost/bin/python)
cd <git_clone_location>/xgboost/python-package
python setup.py install
(This can take around 10 mins)

Test xgboost:
open a python session
Try import xgboost as xgb

Finally, set up Jupyter notebook:
If you want to access xgboost via Kernel > Change Kernel in Jupyter:
conda install jupyter

Helpful reference:
https://www.ibm.com/developerworks/community/blogs/jfp/entry/Installing_XGBoost_on_Mac_OSX?lang=en

Simple git workflow

Git commands

git <command> --help

git log

git status

git add <files/folders>

(undo add: git reset HEAD <files/folders>)

git commit -a --message=<msg>

git pull

git push

Useful Software

What	Link	Description
Recommended and official Git Bash console client	https://git-scm.com/downloads	Windows, OSX and Linux. Good to have this in addition to another client.
Recommended git GUI	https://www.gitkraken.com/download	Windows, OSX and Linux
Github desktop	https://desktop.github.com/	Windows and OSX
Windows shell interface (like TortiseSvn)	https://tortoisegit.org/	Windows only

Installing Java on RHEL with alternatives

Solid post on installing Java 8 on CentOS/RHEL:
http://tecadmin.net/install-java-8-on-centos-rhel-and-fedora/#


Find java download link
http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

Downloading Latest Java Archive
cd /usr/java/ (or your taget directory)
wget --no-cookies --no-check-certificate --header "Cookie: gpw_e24=http%3A%2F%2Fwww.oracle.com%2F; oraclelicense=accept-securebackup-cookie" "http://download.oracle.com/otn-pub/java/jdk/8u91-b14/jdk-8u91-linux-x64.tar.gz"
tar xzf jdk-8u91-linux-x64.tar.gz

Install Java with Alternatives
cd /usr/java/jdk1.8.0_91/
alternatives --install /usr/bin/java java /usr/java/jdk1.8.0_91/bin/java 2
alternatives --config java

Optionally include javac and jar:
alternatives --install /usr/bin/jar jar /usr/java/jdk1.8.0_91/bin/jar 2
alternatives --install /usr/bin/javac javac /usr/java/jdk1.8.0_91/bin/javac 2
alternatives --set jar /usr/java/jdk1.8.0_91/bin/jar
alternatives --set javac /usr/java/jdk1.8.0_91/bin/javac

Check Installed Java Version
java -version

Configuring Environment Variables
export JAVA_HOME=/usr/java/jdk1.8.0_91
export JRE_HOME=/usr/java/jdk1.8.0_91/jre
export PATH=$PATH:/usr/java/jdk1.8.0_91/bin:/usr/java/jdk1.8.0_91/jre/bin




Follow blog post for more env config steps.