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now_dt <- ymd_hms(now(), tz="IST") now_dt ## [1] "2016-07-22 13:53:09 IST" round_date() takes a date-time object and rounds it to the nearest integer value of the specified time unit. round_date(now_dt, "minute") ## [1] "2016-07-22 13:53:00 IST" r...

Unlike durations, periods can be used to accurately model clock times without knowing when events such as leap seconds, leap days, and DST changes occur. start_2012 <- ymd_hms("2012-01-01 12:00:00") ## [1] "2012-01-01 12:00:00 UTC" # period() considers leap year calculati...

with_tz returns a date-time as it would appear in a different time zone. nyc_time <- now("America/New_York") nyc_time ## [1] "2016-07-22 05:49:08 EDT" # corresponding Europe/Moscow time with_tz(nyc_time, tzone = "Europe/Moscow") ## [1] "2016-07-22 12:49:...

CSS: div{ width: 200px; height: 200px; background: teal; clip-path: circle(30% at 50% 50%); /* refer remarks before usage */ } HTML <div></div> This example shows how to clip a div to a circle. The element is clipped into a circle whose radius is 30% based on the dim...

GROUP BY is used in combination with aggregation functions. Consider the following table: orderIduserIdstoreNameorderValueorderDate143Store A2520-03-2016257Store B5022-03-2016343Store A3025-03-2016482Store C1026-03-2016521Store A4529-03-2016 The query below uses GROUP BY to perform aggregated calc...

-XXaggressive is a collection of configurations that make the JVM perform at a high speed and reach a stable state as soon as possible. To achieve this goal, the JVM uses more internal resources at startup; however, it requires less adaptive optimization once the goal is reached. We recommend that y...

This option allows you to clear a TLA for references and values at TLA allocation time and pre-fetch the next chunk. When an integer, a reference, or anything else is declared, it has a default value of 0 or null (depending upon type). At the appropriate time, you will need to clear these references...

When used with -XXallocClearChunkSize, this option sets the size of the chunks to be cleared. If this flag is used but no value is specified, the default is 512 bytes. Usage: -XXallocClearChunks -XXallocClearChunkSize=<size>[k|K][m|M][g|G]

kotlin-gradle-plugin is used to compile Kotlin code with Gradle. Basically, its version should correspond to the Kotlin version you want to use. E.g. if you want to use Kotlin 1.0.3, then you need to aplly kotlin-gradle-plugin version 1.0.3 too. It's a good idea to externalize this version in gradl...

Protocol Oriented Programming is a useful tool in order to easily write better unit tests for our code. Let's say we want to test a UIViewController that relies on a ViewModel class. The needed steps on the production code are: Define a protocol that exposes the public interface of the class Vi...

#include <stdio.h> void print_all(FILE *stream) { int c; while ((c = getc(stream)) != EOF) putchar(c); } int main(void) { FILE *stream; /* call netstat command. netstat is available for Windows and Linux */ if ((stream = popen("netstat", &qu...

The POSIX C library defines the getline() function. This function allocates a buffer to hold the line contents and returns the new line, the number of characters in the line, and the size of the buffer. Example program that gets each line from example.txt: #include <stdlib.h> #include <s...

import ( "io/ioutil" "path/filepath" "gopkg.in/yaml.v2" ) func main() { filename, _ := filepath.Abs("config/config.yml") yamlFile, err := ioutil.ReadFile(filename) var config Config err = yaml.Unmarshal(yamlFile, &c...

String hubUrl = "http://localhost:4444/wd/hub" DesiredCapabilities capability = DesiredCapabilities.firefox(); //or which browser you want RemoteWebDriver driver = new RemoteWebDriver(hubUrl, capability);

Creating a hub A quick configuration for a hub and node setup in selenium grid. For more information see: Grid 2 docs Requirements To set up a grid hub you need the flowing: Selenium-server-standalone-.jar Creating the hub To Create a Hub you need to run the selenium server. Download Se...

Extension methods are useful for adding functionality to enumerations. One common use is to implement a conversion method. public enum YesNo { Yes, No, } public static class EnumExtentions { public static bool ToBool(this YesNo yn) { return yn == YesNo.Yes; ...

Using a custom inspector allows you to change the way a script is drawn in the Inspector. Sometimes you want to add extra information in the inspector for your script that isn't possible to do with a custom property drawer. Below is a simple example of a custom object that with using a custom inspe...

Sometimes you have custom objects that contain data but do not derive from MonoBehaviour. Adding these objects as a field in a class that is MonoBehaviour will have no visual effect unless you write your own custom property drawer for the object's type. Below is a simple example of a custom object,...

By default, the navigation pattern works like a stack of pages, calling the newest pages over the previous pages. You will need to use the NavigationPage object for this. Pushing new pages ... public class App : Application { public App() { MainPage = new NavigationPage(new ...

In CSS3, we can stack multiple background in the same element. #mydiv { background-image: url(img_1.png), /* top image */ url(img_2.png), /* middle image */ url(img_3.png); /* bottom image */ background-position: right bottom, ...