pythonicrubyist

# nil? can be used on any Ruby object. It returns true only if the object is nil.
nil.nil?   # => true 
[].nil?    # => false 
{}.nil?    # => false
"".nil?    # => false
" ".nil?   # => false
true.nil?  # => false

# empty? can be used on some Ruby objects including Arrays, Hashes and Strings. It returns true only if the object's length is zero.
nil.empty?   # NoMethodError: undefined method `empty?' for nil:NilClass

pythonicrubyist

sudo apt-get install dkms build-essential linux-headers-generic
# On virtual machine’s menu bar on top, click on Device/Install Guest Additions. This will launch a unix script runing on the Ubuntu terminal.
sudo reboot

pythonicrubyist

sudo apt-get install libatlas-base-dev
sudo apt-get install gfortran
sudo apt-get install python-matplotlib

sudo pip install numpy
sudo pip install pandas
sudo pip install scipy
sudo pip install patsy
sudo pip install matplotlib
sudo pip install jinja2

pythonicrubyist

data = [('SFO', 'HKO'), ('YYZ', 'SFO'), ('YUL', 'YYZ'), ('HKO', 'ORD')]

# extract nodes
nodes = list(set([val for s in data for val in s]))

# build a graph
graph = {}
for n in nodes:
    graph[n] = []
    paths = [path for path in data if n in path]

pythonicrubyist

# Installing RVM and Ruby:
sudo apt-get install curl
\curl -L https://get.rvm.io | bash -s stable --ruby
echo 'source $HOME/.rvm/scripts/rvm' >> ~/.bashrc
source ~/.bashrc
rvm requirements
rvm install 1.8.7-p371
rvm install 1.9.3-p125
rvm --default use ruby-1.9.3-p125

pythonicrubyist

# List all processes dynamically, q to close top, k to kill a process
top

# Displays processes in tree format
pstree

# Display all running processes owned by the current user
# ps aux

# Find a process

pythonicrubyist

udo apt-get install tcptrack
sudo tcptrack -i eth0 -f

pythonicrubyist

sudo apt-get install python-pip
sudo apt-get install python-setuptools
sudo apt-get install python-dev
sudo apt-get install  build-essential

sudo pip install virtualenv
sudo pip install virtualenvwrapper

sudo echo 'export WORKON_HOME=$HOME/.virtualenvs' >> ~/.bashrc
sudo echo 'source /usr/local/bin/virtualenvwrapper.sh' >> ~/.bashrc

pythonicrubyist

ls *.txt | wc -l | tee /dev/tty count.txt

pythonicrubyist

// Actions are method invocations from View to View Controller.
// Outlets are method invocations from View Controller to view.

// Initial Setup for ViewControllers

// ViewDidLoad - Called when you create the class and load from xib. Great for initial setup and one-time-only work.
// ViewWillAppear - Called right before your view appears, good for hiding/showing fields or any operations that you want to happen every time before the view is visible. Because you might be going back and forth between views, this will be called every time your view is about to appear on the screen.
// ViewDidAppear - Called after the view appears - great place to start an animations or the loading of external data from an API.
// ViewWill/DidDisappear - Same idea as WillAppear.
// ViewDidUnload/ViewDidDispose - In Objective C, this is where you do your clean-up and release of stuff, but this is handled automatically so not much you really need to do here.