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The following example shows how to use a QTimer to call a slot every 1 second. In the example, we use a QProgressBar to update its value and check the timer is working properly. main.cpp #include <QApplication> #include "timer.h" int main(int argc, char *argv[]) { QApp...

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&...

The Chef documentation can be found at https://docs.chef.io/

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...

These are the datepart values available to date & time functions: datepartAbbreviationsyearyy, yyyyquarterqq, qmonthmm, mdayofyeardy, ydaydd, dweekwk, wwweekdaydw, whourhhminutemi, nsecondss, smillisecondmsmicrosecondmcsnanosecondns NOTE: Use of abbreviations is generally discouraged as they c...

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...

DATEPART returns the specified datepart of the specified datetime expression as a numeric value. DATENAME returns a character string that represents the specified datepart of the specified date. In practice DATENAME is mostly useful for getting the name of the month or the day of the week. There a...

One approach that is employed often is to use bootstrap's gridded framework in order to define the area that the chart will exist in. Using this in conjunction with clientWidth variable and the window.onresize event, it is very easy to create responsive d3 SVGs. Let's first create a row and a colum...

Some properties can take multiple values, collectively known as a property list. /* Two values in this property list */ span { text-shadow: yellow 0 0 3px, green 4px 4px 10px; } /* Alternate Formatting */ span { text-shadow: yellow 0 0 3px, green 4px 4px 10px; } ...

@media print { p { page-break-inside: avoid; } h1 { page-break-before: always; } h2 { page-break-after: avoid; } } This code does 3 things: it prevents a page break inside any p tags, meaning a paragraph will never be broken in two pages, if possible. it for...

The most basic instance of an if construct evaluates a condition and executes some code according to the condition outcome. If the condition returns true, the code within the conditional is executed. counter = 10 if counter is 10 console.log 'This will be executed!' The if construct can be e...

To start using Spring data JPA, you must include the dependency in your project with the one of Spring core, all together. If you're using Maven as dependency management system (replace version-number for the version you want to use): <dependencies> <dependency> <groupI...

add_action( 'wp_enqueue_scripts', 'enqueue_my_styles_and_scripts' ); /** * Enqueue scripts (or styles) conditionally. * * Load scripts (or stylesheets) specifically for IE. IE10 and above does * not support conditional comments in standards mode. * * @link https://gist.github.com/wpsc...

Icicle uses Awaitables and Generators to create Coroutines. require __DIR__ . '/vendor/autoload.php'; use Icicle\Awaitable; use Icicle\Coroutine\Coroutine; use Icicle\Loop; $generator = function (float $time) { try { // Sets $start to the value returned by microtime() after ap...

A common refrain in R goes along these lines: You should not have a bunch of related tables with names like DT1, DT2, ..., DT11. Iteratively reading and assigning to objects by name is messy. The solution is a list of tables of data! Such a list looks like set.seed(1) DT_list = lapply(setNam...

Unzipping a zip archive is done with unzip function from the utils package (which is included in base R). unzip(zipfile = "bar.zip", exdir = "./foo") This will extract all files in "bar.zip" to the "foo" directory, which will be created if necessary. Tilde...

Listing files in a zip archive is done with unzip function from the utils package (which is included in base R). unzip(zipfile = "bar.zip", list = TRUE) This will list all files in "bar.zip" and extract none. Tilde expansion is done automatically from your working directory. ...

Codeigniter may be configured to run more than one project without duplicating CI core files. It's possible by splitting CI Application side. For example let's take project of website, which contains front-end and back-end Content Management System (CMS) applications. In this case CI folder struct...

Vlookup finds some value in the leftmost column of a range and returns a value some number of columns to the right and in the same row. Let's say you want to find the surname of Employee ID 2 from this table: =VLOOKUP(2,$A$2:$C$4,3,0) The value you're retrieving data for is 2 The table you...