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For the sake of this example, let us assume that we have a server for handling the POST requests that we will be making from our Android app: // User input data. String email = "my@email.com"; String password = "123"; // Our server URL for handling POST requests. String UR...

Casting: The Basics Casting is used to transform data from long to wide format. Starting with a long data set: DT = data.table(ID = rep(letters[1:3],3), Age = rep(20:22,3), Test = rep(c("OB_A","OB_B","OB_C"), each = 3), Result = 1:9) We can cast our data using the...

The FETCH clause was introduced in Oracle 12c R1: SELECT val FROM mytable ORDER BY val DESC FETCH FIRST 5 ROWS ONLY; An example without FETCH that works also in earlier versions: SELECT * FROM ( SELECT val FROM mytable ORDER BY val DESC ) WHERE ROWNUM <= 5;

One of the nicest features of flexbox is to allow optimally fitting containers to their parent element. Live demo. HTML: <div class="flex-container"> <div class="flex-item">1</div> <div class="flex-item">2</div> <div class=&q...

The pointer-events property allows for control over how HTML elements respond to mouse/touch events. .disabled { pointer-events: none; } In this example, 'none' prevents all click, state and cursor options on the specified HTML element [[1]] Other valid values for HTMl elements are: ...

Having a global allows for better DRYness, you need only put values that are different into AssemblyInfo.cs for projects that have variance. This use assumes your product has more than one visual studio project. GlobalAssemblyInfo.cs using System.Reflection; using System.Runtime.InteropServices...

2.12.2 You can use the minElement() and maxElement() methods to find the minimum or maximum element in a given sequence. For example, with an array of numbers: let numbers = [2, 6, 1, 25, 13, 7, 9] let minimumNumber = numbers.minElement() // Optional(1) let maximumNumber = numbers.maxElement()...

Often beginning MATLAB developers will use MATLAB's editor to write and edit code, in particular custom functions with inputs and outputs. There is a Run button at the top that is available in recent versions of MATLAB: Once the developer finishes with the code, they are often tempted to push th...

Explicite selection A plotting style is usually selected using the with keyword, like plot x with points This allows to use different plotting styles for every plot: plot x with points, 2*x with lines Typing help with in the gnuplot command window gives a list of all available plotting styl...

ActiveRecord with includes ensures that all of the specified associations are loaded using the minimum possible number of queries. So when querying a table for data with an associated table, both tables are loaded into memory. @authors = Author.includes(:books).where(books: { bestseller: true } ) ...

To build a Rails application that will be an API server, you can start with a more limited subset of Rails in Rails 5. To generate a new Rails API app: rails new my_api --api What --api does is to remove functionality that is not needed when building an API. This includes sessions, cookies, ass...

We can add Kendo-UI grid in HTML5/Javascript, ASP.NET MVC, JSP and PHP project/application. Please follow below steps to add kendo-UI grid in HTML5 page. Create empty html5 page. Include kendo.common.min.css and kendo.default.min.css. Add a link tag within the head tag. Kendo-UI li...

Consider the following naive method for adding two positive numbers using recursion: public static int add(int a, int b) { if (a == 0) { return b; } else { return add(a - 1, b + 1); // TAIL CALL } } This is algorithmically correct, but it has a major problem. ...

Manually open and close a file. # Using new method f = File.new("test.txt", "r") # reading f = File.new("test.txt", "w") # writing f = File.new("test.txt", "a") # appending # Using open method f = open("test.txt", "r&...

If you're just getting started with Chef, we recommend starting off with our Learn Chef tutorial at http://learn.chef.io/. If you have questions during or after that, check out or discussion forum/mailing list at https://discourse.chef.io/ or our public Slack team at https://community-slack.chef.io...

We request that the Chef community not use this StackOverflow documentation feature. Docs managed via wiki (or community editing in general) tend to rot very quickly and are of poor quality. We've all experienced the sense of dread when searching for an answer on Google and getting back a half-unrea...

For immutable elements (e.g. None, string literals etc.): my_list = [None] * 10 my_list = ['test'] * 10 For mutable elements, the same construct will result in all elements of the list referring to the same object, for example, for a set: >>> my_list=[{1}] * 10 >>> print(my_...

General syntax: DATEADD (datepart , number , datetime_expr) To add a time measure, the number must be positive. To subtract a time measure, the number must be negative. Examples DECLARE @now DATETIME2 = GETDATE(); SELECT @now; --2016-07-21 14:39:46.4170000 SELECT DAT...

General syntax: DATEDIFF (datepart, datetime_expr1, datetime_expr2) It will return a positive number if datetime_expr is in the past relative to datetime_expr2, and a negative number otherwise. Examples DECLARE @now DATETIME2 = GETDATE(); DECLARE @oneYearAgo DATETIME2 = DATEADD(YEAR, -1, @now...

Using the DATEADD and DATEDIFF functions, it's possible to return the last date of a month. SELECT DATEADD(d, -1, DATEADD(m, DATEDIFF(m, 0, '2016-09-23') + 1, 0)) -- 2016-09-30 00:00:00.000 SQL Server 2012 The EOMONTH function provides a more concise way to return the last date of a month, and...