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A circle is a closed shape formed by tracing a point that moves in a plane such that its distance from a given point is constant. In this article we will check how to form the equation of circle from given radius and centre. We will be given a circle with point i.e (x, y), radius r and centre i.e (x1, y1). We need to form the equation of circle from given radius and centre. The equation of the circle is given by formula − $$\mathrm{(x\:-\:x1)^2\:+\:(y\:-\:y1)^2\:=\:r^2}$$ Where, (x, y) is a point. (x1, y1) is centre. And r ... Read More
Introduction Memory management is a crucial part of computer systems that deals with managing memory resources. Memory is where computers store data, instructions, and programs while they are being used. Managing memory is important for the computer system to run smoothly. In this article, we will discuss what memory management is, and its benefits and drawbacks. Memory Management Memory management is a crucial task for the operating system, as it is responsible for managing the allocation and release of memory for different applications and processes. The operating system divides memory into different areas and assigns these regions to the applications ... Read More
Introduction Some operating systems use memory ballooning to optimize memory usage in virtualized environments. It entails dynamically reallocating memory resources among virtual machines (VMs) based on their current requirements. In this article, we will explore what is Memory Ballooning, and its advantages and disadvantages in detail. Memory Ballooning Memory ballooning is a technique used in virtualized environments to optimize the use of memory resources. It allows the operating system to reclaim unused memory from one virtual machine and allocate it to another that requires it. This helps to prevent resource waste and improves overall performance. Memory ballooning is achieved through ... Read More
Introduction In computer science and operating systems, memory allocation techniques are used to allocate memory to programs and processes. The mapping of virtual addresses to physical addresses is an important aspect of memory allocation because it allows programs to access the memory they require to run. Mapping Virtual Addresses to Physical Addresses Virtual addresses are used by programs to access memory, while physical addresses are the actual locations in RAM where data is stored.Memory allocation techniques manage the mapping of virtual addresses to physical addresses using different methods. Methods of Mapping Virtual Addresses to Physical Addresses There are three common ... Read More
What is Savefrom.net? Savefrom.net is an online video downloader which allows you to download videos from different websites like YouTube. There is no need to install any software for downloading videos. The service can be used without making any payment. No registration is required to use the service. Because of all these features, the service gets millions of traffic per month. You just need to copy the URL of the video and click the Download button to download videos. Cost of Savefrom.net Savefrom.net is free of cost and you can download any number of videos daily through this service. Why ... Read More
In Swift, the viewDidAppear method does not call when an application is opened from the background. In that case, you have to use the applicationWillEnterForeground method in the AppDelegate. In this article, you will see an example of how to perform an action when opening an app from the background. Approach If you open an app from the background, it should call the applicationWillEnterForeground method of the app delegate before presenting the view. However, it's possible that the viewDidAppear method of the view controller is not called if the view controller's view is already on the screen or if the ... Read More
In Swift, an optional escaping closure parameter is a closure that can be executed after the function it is passed to has returned. In this article, we will see how to create escaping closures as parameters with examples. To declare an optional escaping closure parameter, you add the @escaping keyword before the closure type to the function's parameter list. Syntax Here is the syntax. func doSomething(completion: @escaping () -> Void) { // Write code here } In the above code, completion is an optional escaping closure parameter that takes no parameters and returns Void. The @escaping ... Read More
In Swift, there are many approaches to converting an integer to time components like hours, minutes, and seconds. Every approach depends on the requirement. For example, you can use arithmetic operators to convert. Another approach is using DateComponentsFormatter class to convert an integer into time components easily. In this article, you will see many examples of converting an integer to time components. Example 1 To convert an integer representing a duration in seconds to hours, minutes, and seconds, you can use the following code in Swift − import Foundation let durationInSeconds = 3661 let hours = durationInSeconds / 3600 let ... Read More
In Swift, the do-try-catch statement is used to handle errors that can be thrown by a function or method. It provides a structured way to catch and handle errors in your code. In your codebase, you cannot handle all runtime errors when they come but using try-catch you can handle them without crashing your application. The do-try-catch Syntax The do block is used to wrap code that could throw an error. Inside the do block, you call the function or method that throws an error. The try keyword is used before calling any function or method that may throw an ... Read More
In Swift, you can use KVO to observe changes to an object property by registering an observer for that property. When the property value changes, the observer is notified and can take appropriate actions. In this article, you will see an example of how to implement KVO in Swift. To use KVO in Swift, you need to do the following Mark the property that you want to observe with the @objc dynamic attribute. This attribute tells the Swift compiler to generate Objective-C-compatible code for the property. Register an observer for the property using the addObserver(_:forKeyPath:options:context:) method of the observed ... Read More