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import sympy as sy # Symbols have to be defined before one can use them x = sy.S('x') # Definition of the equation to be solved eq=sy.Eq(x**2 + 2, 6) #Print the solution of the equation print sy.solve(eq) The result printed will be: [-2, 2]

This example is divided into two pillars SalaryCalculation Class : Calculating the net salary after tax deduction SalaryCalculationTests Class : For testing the method that calculates the net salary Step 1: Create Class Library, name it WagesLibrary or any appropriate name. Then rename the cl...

By default Controllers, ViewComponents and TagHelpers aren't registered and resolved via the dependency injection container. This results in the inability to do i.e. property injection when using a 3rd party Inversion of Control (IoC) container like AutoFac. In order to make ASP.NET Core MVC resolv...

Prerequisites Have a strong grasp of a programming language such as Python, C, C++, Ruby, or any of the other languages out there. Have your favorite code editor or IDE installed (one such example is VSCode) Stay motivated. Constructing a compiler is not easy, so keep pushing; it's worth the ef...

Configuration Log4j configuration file can be in any of these formats: JSON YAML properties (text file) XML Configuration discovery Log4j will inspect the log4j.configurationFile system property and, if set, will attempt to load the configuration. If no system property is set log4j wil...

For example, we have two environments: CI - Staging and want to add some customizations for each environment. Here I will try to customize server URL, app name. First, we create two targets for 2 environments by duplicating the main target: For each target, we will define a custom macro. Here I ...

C++ #include "opencv2/objdetect/objdetect.hpp" #include "opencv2/highgui/highgui.hpp" #include "opencv2/imgproc/imgproc.hpp" #include <iostream> #include <stdio.h> using namespace std; using namespace cv; // Function Headers void detectAndDisp...

There is a useful package in Python - chardet, which helps to detect the encoding used in your file. Actually there is no program that can say with 100% confidence which encoding was used - that's why chardet gives the encoding with the highest probability the file was encoded with. Chardet can dete...

You can nest enumerations one inside an other, this allows you to structure hierarchical enums to be more organized and clear. enum Orchestra { enum Strings { case violin case viola case cello case doubleBasse } enum Keyboards { case...

Animation to show how selection sort works Below example shows selection sort in ascending order: public class MySelectionSort { public static int[] doSelectionSort(int[] arr){ for (int i = 0; i < arr.length - 1; i++) { int index = i; ...

Many Flask applications are developed in a virtualenv to keep dependencies for each application separate from the system-wide Python installation. Make sure that mod-wsgi is installed in your virtualenv: pip install mod-wsgi Then create a wsgi wrapper for your Flask application. Usually it's kep...

The advantage of using Apache over the builtin werkzeug server is that Apache is multi-threaded, meaning that multiple connections to the application can be made simultaneously. This is especially useful in applications that make use of XmlHttpRequest (AJAX) on the front-end. /etc/apache2/sites-ava...

To set the environment to Development SET ASPNETCORE_ENVIRONMENT=Development Now running an Asp.Net Core application will be in the defined environment. Note There should be no space before and after the equality sign =. The command prompt should not be closed before running the application b...

Homebrew calls itself 'the missing package manager for macOS'. It can be used to build and install applications and libraries. Once installed, you can use the brew command to install PostgreSQL and it's dependencies as follows: brew update brew install postgresql Homebrew generally installs the...

# ... # same as above @app.route('/welcome/<name>') def welcome(name): return render_template('main.html', name=name) @app.route('/login', methods=['GET', 'POST']) def login(): if request.method == 'POST': # ... # check for valid login, assign username ...

Multiton can be used as a container for singletons. This is Multiton implementation is a combination of Singleton and Pool patterns. This is an example of how common Multiton abstract Pool class can be created: abstract class MultitonPoolAbstract { /** * @var array */ protec...

This pattern can be used to contain a registered Pools of Singletons, each distinguished by unique ID: abstract class MultitonRegistryAbstract { /** * @var array */ protected static $instances = []; /** * @param string $id */ final protected function ...

To use auto layout we need to enable a boolean flag in storyboard. Its shown in the below image. After this we can use auto layout in our storyboard. There is another option if we want to use size classes or not. Size class is also a helpful option in auto layout which helps us to design for differe...

To enable the ripple animation in a CardView, add the following attributes: <android.support.v7.widget.CardView ... android:clickable="true" android:foreground="?android:attr/selectableItemBackground"> ... </android.support.v7.widget.CardView>

Passing a 2d array to a functions seems simple and obvious and we happily write: #include <stdio.h> #include <stdlib.h> #define ROWS 3 #define COLS 2 void fun1(int **, int, int); int main() { int array_2D[ROWS][COLS] = { {1, 2}, {3, 4}, {5, 6} }; int n = ROWS; int m...