Programming Leftovers

posted by Roy Schestowitz on Aug 24, 2022

Java

• How to Check if a Character is a Number in Java

  Java comprises a class named Character, which belongs to java.lang package. The object of the Character class contains a single field “char” that is a primitive datatype in Java. A Java char has a 16-bit size, with a range of 0 to 65,536 characters. The data type char belongs to the characters group, a character set representing symbols such as alphabets and numerals.

  This guide will discuss the method of checking if the specified character is a number or not.

• Different Ways to Call a Method in Java

  In Java, a method is a combination of logical statements utilized to perform specific operations. Methods are commonly used because their added code can be reused as often as needed. Each method in Java is called using its name, and when the Java compiler reads it, the mentioned method is invoked, and the added operational code gets executed.

  This tutorial will illustrate different ways of calling methods in a Java program.

C/C++

• Mike Blumenkrantz: Continuous

  As of this moment, Mesa is now using the Mold linker in CI for faster build times.

  If you haven’t tried Mold yet, you’re just pointlessly wasting your own time.

• C++ std::mutex/

  By using the Mutex keyword, we may lock our variable from being accessed by several threads at once. Mutex is utilized to provide synchronization in C++, meaning only one thread can receive the object at once. Threads cannot access the locked piece of code once the lock has been established. The code has been locked using mutexes. So, even if thread 2 is scheduled while thread 1 is still consuming the shared resource, thread 2 will not be able to access that part of the code. As a result, synchronized access to shared resources in the code is ensured.

• C++ ofstream Functions

  Data is stored locally on computers through file handling. We may insert the content in secondary memory by managing files.

• C++ Pair Functions

  In this guide, we’ll examine pair containers in C++ and their applications. In C++ Programming language, a pair container works similarly to a tuple. However, a pair could only contain two elements, whereas a tuple can contain many elements. The two components could have multiple data types or similar data types like a tuple. Pair is a container that is given by the <utility> module and is declared in C++ Programming language by utilizing the term ‘pair’. So, in essence, a pair is utilized to combine two components or integers within one. This enables the storage of heterogeneous elements or multiple data kinds as a single entity.

• C++ std::thread Functions

  A process’s single sequence stream can be termed a thread. Threads are frequently referred to as “lightweight processes” since they have some characteristics with processes. A class is to represent distinct execution threads. A single thread of execution is represented by the class thread. Multiple functions can run at once because of threads. When a thread object is created, it instantly starts to execute (subject to any OS scheduling delays) starting at the highest function specified as a function constructor. The method’s defined value is disregarded and std::terminate is invoked if it exits by raising an error.

• C++ New Operator

  We will cover how to efficiently manage allocation in C++ utilizing the ‘new’ function through the use of practical examples.

  In C++, the term “dynamic memory deployment” refers to the manual allotment of storage by a programmer. Heap is where distributed shared memory is deployed, while Stack is where non-static and local variables acquire memory resources.

• C++ istream Functions

  The term “stream” in C++ describes the flow of characters between the program thread and i/o. C++ stream classes are needed to input and output actions on IO devices and files. These classes are designed to manage the program’s input and output and they have particular functionality.

Python

• Inheritance in Python

  When we create new classes, we can inherit methods and attributes from previously developed classes. These attributes are found in data structures that have been specified, as well as in the procedures that may be used to accomplish different functions. As the codebase becomes more modular, this encourages code reuse, which is regarded as one of the most significant industrial coding techniques. Newer classes in Python can inherit older classes. Without altering the older or previous class’s syntax, the new class or classes replicate all of its properties and functions into themselves. The term “base class” refers to the original classes and “derived classes” refers to the new classes.

  The term “inheritance” is frequently used to refer to the passing of some essential functions from one generation to the next. Like parent classes, there are child and base classes. We create classes through inheritance by deriving them from other pre-existing classes. The parent/base classes, by which the child classes acquire their methods and attributes, are the already existent classes.

• Tkinter Listbox

  The default GUI toolkit for Python is called Tkinter. The combination of Python with Tkinter makes it quick and simple to develop the GUI apps. An effective object-oriented gateway for the Tk GUI toolkit is provided by Tkinter. It’s simple to build a Gui interface employing the Tkinter. Within this guide, we will show you the use of the Tkinter library to create a Tkinter GUI and add a Listbox widget to it.

  Getting started with the Ubuntu 20.04 system, we update our system using some commands in the terminal shell. We launch the terminal application with the Ctrl+Alt+T and add the apt “update” instruction on it. The execution requires the password of the logged-in user and it updates the whole system after the addition of a password.

• Tkinter ComboBox

  The ttk package, a unique modification of Python Tkinter, introduces this additional component. The Python Tkinter ComboBox exhibits each choice from a drop-down menu 1 at a moment. It has a contemporary appearance, making it suitable for locations where exposure is crucial. The gadget Entry is a class ability of the Python ComboBox. As a result, it adds some additional choices and functions while also inheriting several from the Entry class.

  A crucial widget that may be seen in several programs is the ComboBox. The user is given a list of alternatives to choose from. It has several values, and only ever displays one at a moment. Today’s tutorial will cover how to use the ComboBox in Linux using Tkinter.

• Tkinter CheckBox

  To create applications using Graphical User Interfaces (GUIs), Python offers a variety of libraries. The industry-standard GUI package, Tkinter, offers a quick and simple approach to developing GUI programs. This GUI toolkit for TCL (Tool Command Language) is unique. The simplicity of Tkinter is one of its greatest advantages. It comes with a large range of necessary widgets practically to everyday operations.

  The Checkbutton widget is employed to present a user with a range of substitutes as toggle switches. By hitting the button beside each choice, the viewer can then choose one or more of them. Within this article, we will take a look at the Python’s Tkinter library to create the checkboxes in a graphical user interface. Getting started with this article, we have to make sure that the “Tkinter” utility of Python is already configured at our end. If not, try the following instruction in the console application query area.

TeX

• How To Create A Bold Text in LaTeX

  Bolding a text helps highlight specific content for readers. The bold option makes a text thicker than others to emphasize it. In any article, research paper, technical and non-technical document, you can use bold text to draw attention to the relevant information.

  Using bold text in a document is good, but LaTeX doesn’t offer a simple way to bold a text since it requires the correct source code. Read this guide if you are interested in learning how to create bold text in LaTeX.

• How To Use the Perpendicular Symbol in LaTeX

  The ⊥ symbol indicates two perpendicular lines. Suppose m and n are two traces dividing by 90, then perpendicular to each other and represented as m ⊥ n. In the concept of perpendicular, a point of intersection of both lines is called the foot of the vertical.

  You can use the perpendicular symbol in the document processor like LaTeX. However, it requires a correct source code. So, in this tutorial, we will explain different source codes you can use to use perpendicular symbols in LaTeX.

• How To Use Prime Symbols in LaTeX

  A prime symbol (‘) denotes a specific operation at a particular variable. This symbol is used as a standard quotation mark to indicate a specific value as well. In Mathematics, a prime symbol represents feet or arc minutes. Similarly, the double prime symbol (“) shows the inches and arcsecs.

  Prime symbols are also used to describe the derivative of a function f(x). So, these symbols have an essential role in Mathematics. That’s why LaTeX also offers a way to use prime symbols. If you also want to learn how to write and use a prime symbol in LaTeX, read this tutorial for more information and examples.

• How To Use Landscape Page in LaTeX

  A landscape mode on any document processor is essential in efficiently representing large images, tables, and texts. Portrait mode has a few limitations, such as being unable to fit wide photos. Technical documents like research papers require large tables and diagrams to provide in-depth information. That’s why document processors, like LaTeX, provide methods to turn your pages from portrait to landscape.

  Read this tutorial if you are also interested in learning how to use a landscape page in LaTeX. This tutorial will explain creating and using a landscape page in LaTeX.

• How To Use a Sigma Symbol in LaTeX

    In Algebra, the sigma symbol (Σ) indicates the summation operator. The symbol, Σ, offers the simplest form of writing the sum of components in a series. In mathematics, the sigma symbol is used to indicate a sum. The simple (Σ) and double (ΣΣ) are two sigma symbols you can use in Algebra.

  The simple sigma symbol is used to express a sum of multiple values, while the double sigma symbol is used as the double sum in a specific situation. Hence, it is essential to write the sigma symbol when you are writing a research paper or a document. This tutorial will demonstrate how to write and use sigma symbols in LaTeX.

• How To Use a Congruent Symbol LaTeX

  The congruent symbol in mathematics is used to show similarities between triangles. The symbol (≅) is a combination of the equal (=) and tilde (~) symbols. A congruent symbol is one of geometry’s most commonly used symbols, representing the relation between the triangles.

  This symbol may look simple, but many users occasionally become confused while writing it to the document processor. You may already know LaTeX (document processor) requires source code to create a congruent symbol. So, in this tutorial, we will explain a simple way to write and use a congruent symbol in LaTeX.

• How To Create an Italic Text in LaTeX

  In articles, italic text is mainly used to emphasize a particular segment to draw a reader’s attention. Text editors, like MS Word and Google Docs, provide the simplest way to italicize text. You only have to press CTRL and I to italicize a text. However, the document processor doesn’t contain the same way as it requires a proper source code formation.

  That’s why many users don’t know how to italicize a text in a document processor like LaTeX. If you also face the same issue, then please read this tutorial. This tutorial teaches you how to write italic text in LaTeX.