Tutorial by Examples: al

NA is a logical type and a logical operator with an NA will return NA if the outcome is ambiguous. Below, NA OR TRUE evaluates to TRUE because at least one side evaluates to TRUE, however NA OR FALSE returns NA because we do not know whether NA would have been TRUE or FALSE NA | TRUE # [1] TRUE ...

Microsoft Access is one of the Microsoft Office suite of programs. However, it is only available in some packages of MS Office. If you wish to obtain Access, please make sure to carefully examine the box or download specifications for each version of Microsoft Office. MS Access is only available fo...

Sometimes you may want maintain versions of a git repository on machines that have no network connection. Bundles allow you to package git objects and references in a repository on one machine and import those into a repository on another. git tag 2016_07_24 git bundle create changes_between_tags...

In some cases you might want to add an additional description to an enum value, for instance when the enum value itself is less readable than what you might want to display to the user. In such cases you can use the System.ComponentModel.DescriptionAttribute class. For example: public enum Possibl...

Installing Appcelerator Titanium At first we need to set up Titanium: command-line tools (CLI) to compile the apps the MVC framework Alloy the SDK The main parts are installed using the node.js package manager 'npm'. Check https://nodejs.org/ if you need to install it. Linux (Fedora) If y...

For testing purposes, you can host your blog on your local machine. After setting up and making any changes, Jekyll can server the blog to http://localhost:4000. On the command line in the root directory of the project, run: $ bundle exec jekyll serve The bundle exec part is optional, but if you...

A value of a struct type can be written using a struct literal that specifies values for its fields. type Point struct { X, Y int } p := Point{1, 2} The above example specifies every field in the right order. Which is not useful, because programmers have to remember the exact fields in order. M...

PrestaShop can be download here. You can find system requirements here.

If you want to keep on-premises copy of the Gradle and let the Wrapper use it in the builds, you can set the distributionUrl pointing to your copy on the wrapper task: task wrapper(type: Wrapper) { gradleVersion = '2.0' distributionUrl = "http\://server/dadada/gradle-${gradleVersion}...

Lambdas are meant to provide inline implementation code for single method interfaces and the ability to pass them around as we have been doing with normal variables. We call them Functional Interface. For example, writing a Runnable in anonymous class and starting a Thread looks like: //Old way n...

Since Ionic 2 is getting better and better every day, please always check the official documentation to keep track of the latest changes and improvements. Prerequisites: You will need NodeJS in order to build Ionic 2 projects. You can download and install node here and learn more about npm and the...

One way to calculate the Big-O value of a procedure you've written is to determine which line of code runs the most times in your function, given your input size n. Once you have that number, take out all but the fastest-growing terms and get rid of the coefficents - that is the Big-O notation of yo...

Run the install on a single run command to merge the update and install. If you add more packages later, this will run the update again and install all the packages needed. If the update is run separately, it will be cached and package installs may fail. Setting the frontend to noninteractive and pa...

Lists can populated with any data type as necessary, with the format Dim aList as New List(Of Type) For example: Create a new, empty list of Strings Dim aList As New List(Of String) Create a new list of strings, and populate with some data VB.NET 2005/2008: Dim aList as New List(Of String...

Dim aList as New List(Of Integer) aList.Add(1) aList.Add(10) aList.Add(1001) To add more than one item at a time use AddRange. Always adds to the end of the list Dim blist as New List(of Integer) blist.AddRange(alist) Dim aList as New List(of String) alist.AddRange({"one", &...

Dim aList As New List(Of String) aList.Add("Hello") aList.Add("Delete Me!") aList.Add("World") 'Remove the item from the list at index 1 aList.RemoveAt(1) 'Remove a range of items from a list, starting at index 0, for a count of 1) 'This will remove index 0, ...

Dim aList as New List(Of String) aList.Add("Hello, World") aList.Add("Test") Dim output As String = aList(0) output: Hello, World If you do not know the index of the item or only know part of the string then use the Find or FindAll method Dim aList as New List(Of S...

Let's say you have two commits d9e1db9 and 5651067 and want to see what happened between them. d9e1db9 is the oldest ancestor and 5651067 is the final descendant in the chain of commits. gitk --ancestry-path d9e1db9 5651067

Java provides a conditional-and and a conditional-or operator, that both take one or two operands of type boolean and produce a boolean result. These are: && - the conditional-AND operator, || - the conditional-OR operators. The evaluation of <left-expr> && <righ...

On linux: If you don't have pip installed, install it first: curl "https://bootstrap.pypa.io/get-pip.py" -o "get-pip.py" sudo python get-pip.py Then install awscli: sudo pip install awscli On Windows: Download the latest installers from here