Tutorial by Examples: g

REPL stands for 'Read Evaluate Print Loop.' The REPL can be used to write and execute code one line at a time and is an alternative to writing code to a file and then compiling or interpreting the entire file before execution. To start the SMLNJ REPL from a command prompt: smluser> sml Standar...

The %>% operator can also be used to pipe the dplyr output into ggplot. This creates a unified exploratory data analysis (EDA) pipeline that is easily customizable. This method is faster than doing the aggregations internally in ggplot and has the added benefit of avoiding unnecessary intermediat...

All SML expressions return a value. The REPL stores the return value of the last evaluated expression. it provides the value of the last evaluated expression within the REPL. smluser> sml Standard ML of New Jersey v110.78 [built: Thu Jul 23 11:21:58 2015] - 3+4; val it = 7 : int - it; val i...

You could migrate from team foundation version control to git by using an open source tool called Git-TF. Migration will also transfer your existing history by converting tfs checkins to git commits. To put your solution into Git by using Git-TF follow these steps: Download Git-TF You can downloa...

Worker Node: #Run the following on the worker node to leave the swarm. docker swarm leave Node left the swarm. If the node has the Manager role, you will get a warning about maintaining the quorum of Managers. You can use --force to leave on the manager node: #Manager Node docker swarm l...

In this example we use the save method to save an Animation object using ImageMagick. import numpy as np import matplotlib.pyplot as plt import matplotlib.animation as animation from matplotlib import rcParams # make sure the full paths for ImageMagick and ffmpeg are configured rcParams['ani...

This example will create an EC2 instance of t2.micro type in N.Virginia region running Amazon Linux. During the execution, it will ask to select the KeyPair to use and an I.P. CIDR from where you can SSH to the instance, use default to make SSH open to the internet { "AWSTemplateFormatVersion"...

You can create unlogged tables so that you can make the tables considerably faster. Unlogged table skips writing write-ahead log which means it's not crash-safe and unable to replicate. CREATE UNLOGGED TABLE person ( person_id BIGINT NOT NULL PRIMARY KEY, last_name VARCHAR(255) NOT NULL, ...

To query a field which name is contained in a variable, use the field function. some_field = :id some_value = 10 from p in Post, where: field(p, ^some_field) == ^some_value

To join and and for instance filter on the joined table use JoinQueryOver. IList<Customer> customers = session.QueryOver<Customer>() .Inner.JoinQueryOver(x => x.Organisation) .Where(y => y.Name == "Acme Inc") .List();

For interacting with plots Matplotlib offers GUI neutral widgets. Widgets require a matplotlib.axes.Axes object. Here's a slider widget demo that ùpdates the amplitude of a sine curve. The update function is triggered by the slider's on_changed() event. import numpy as np import matplotlib.pyplot...

If you are new to middleware in Express check out the Overview in the Remarks section. First, we are going to setup a simple Hello World app that will be referenced and added to during the examples. var express = require('express'); var app = express(); app.get('/', function(req, res) { r...

A good VOD (Video On Demand) service should start with the basics. Lets say you have a directory on your server that is not publicly accessible, yet through some sort of portal or paywall you want to allow users to access your media. var movie = path.resolve('./public/' + req.params.filename); ...

You can also use flent-ffmpeg to convert .mp4 files to .flv files, or other types: res.contentType('flv'); var pathToMovie = './public/' + req.params.filename; var proc = ffmpeg(pathToMovie) .preset('flashvideo') .on('end', function () { console.log(...

s/foo/bar/; # replace "foo" with "bar" in $_ my $foo = "foo"; $foo =~ s/foo/bar/; # do the above on a different variable using the binding operator =~ s~ foo ~ bar ~; # using ~ as a delimiter $foo = s/foo/bar/r; # non-destructive r flag: returns the repl...

Implement onMessageReceived that will catch the notification sent from GCM server. @Override public void onMessageReceived(String from, Bundle data) { String message = data.getString("message"); Log.d(TAG, "From: " + from); Log.d(TAG, "Message: "...

To receive the notification, implement application:didReceiveRemoteNotification:fetchCompletionHandler: (or application:didReceiveRemoteNotification: for iOS < 8.0), and call GCMService:appDidReceiveMessage:message to acknowledge the reception of the message to GCM. - (void)application:(UIApplic...

This writeup walks though steps to configure Tomcat to request CAC certificates from the client. It is focused on setting up a development environment, so some features that should be considered for production are not here. (For example it shows using a self-signed certificate for https and it does...

One implementation of the io.Reader interface can be found in the bytes package. It allows a byte slice to be used as the source for a Reader. In this example the byte slice is taken from a string, but is more likely to have been read from a file or network connection. message := []byte("Hello...

Sometimes it may be required to find out which directory consuming how much disk space especially when you are used df -h and realized your available disk space is low. du: du command summarizes disk usage of the set of FILEs, recursively for directories. It's often uses with -sh option: -s, --s...