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import sympy as sy x1, x2 = sy.symbols("x1 x2") equations = [ sy.Eq( 2*x1 + 1*x2 , 10 ), sy.Eq( 1*x1 - 2*x2 , 11 ) ] print sy.solve(equations) # Result: {x1: 31/5, x2: -12/5}

import sympy as sy x, y = sy.symbols("x y") # nsolve needs the (in this case: two) equations, the names of the variables # (x,y) we try to evaluate solutions for, and an initial guess (1,1) for the # solution print sy.nsolve((x**3+sy.exp(y)-4,x+3*y),(x,y),(1,1)) The result s...

Detailed instructions on getting clion set up or installed.

Usage To install a module (assuming cpanm is already installed): cpanm Data::Section cpanm ("cpanminus") strives to be less verbose than cpan but still captures all of the installation information in a log file in case it is needed. It also handles many "interactive questions&quo...

As usual, we first need a CFDictionary to represent the item we want to update. This must contain all of the old values for the item, including the old private data. Then it takes a CFDictionary of any attributes or the data itself that you would like to change. So first, let's construct a class ke...

The JAR, WAR and EAR files types are fundamentally ZIP files with a "manifest" file and (for WAR and EAR files) a particular internal directory / file structure. The recommended way to create these files is to use a Java-specific build tool which "understands" the requirements f...

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...

If the ORDER BY clause is specified in your update SQL statement, the rows are updated in the order that is specified. If LIMIT clause is specified in your SQL statement, that places a limit on the number of rows that can be updated. There is no limit, if LIMIT clause not specified. ORDER BY and L...

In multiple table UPDATE, it updates rows in each specified tables that satisfy the conditions. Each matching row is updated once, even if it matches the conditions multiple times. In multiple table UPDATE, ORDER BY and LIMIT cannot be used. Syntax for multi table UPDATE is, UPDATE [LOW_PRIORITY]...

dispatch_group_t preapreWaitingGroup = dispatch_group_create(); dispatch_group_enter(preapreWaitingGroup); [self doAsynchronousTaskWithComplete:^(id someResults, NSError *error) { // Notify that this task has been completed. dispatch_group_leave(preapreWaitingGroup); }] dispatch...

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...

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...

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...

Assume your data examples are already read to a python's variable and you would like to read it n times, in batches of given size: import numpy as np import tensorflow as tf data = np.array([1, 2, 3, 4, 5]) n = 4 To merge data in batches, possibly with random shuffling, you can use tf.train.b...

OpenCV (Open Source Computer Vision Library) is an open source computer vision and machine learning software library. It was built for various purpose such as machine learning, computer vision, algorithm, mathematical operations, video capturing, image processing etc. Over the years it has become ve...

local collections are not allowed in select statements. Hence the first step is to create a schema level collection. If the collection is not schema level and being used in SELECT statements then it would cause "PLS-00642: local collection types not allowed in SQL statements" CREATE OR R...

When mapping our entities to database table names we rely on a @Table annotation. But if we have a naming convention for our database table names, we can implement a custom physical naming strategy in order to tell hibernate to calculate table names based on the names of the entities, without explic...