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Detailed instructions on getting google-cloud-platform set up or installed.

A NullReferenceException is thrown when you try to access a non-static member (property, method, field or event) of a reference object but it is null. Car myFirstCar = new Car(); Car mySecondCar = null; Color myFirstColor = myFirstCar.Color; // No problem as myFirstCar exists / is not null Color...

PHPUnit provides the following functions to watch for thrown exceptions, which were released with 5.2.0: expectException($exception) expectExceptionMessage($message) expectExceptionCode($code) expectExceptionMessageRegExp($messageRegExp) These are used to watch for an exception to be thrown...

If you need to listen for changes to the page selected you can implement the ViewPager.OnPageChangeListener listener on the ViewPager: viewPager.addOnPageChangeListener(new OnPageChangeListener() { // This method will be invoked when a new page becomes selected. Animation is not necessar...

Problem statement: Find the minimum (over x, y) of the function f(x,y), subject to g(x,y)=0, where f(x,y) = 2 * x**2 + 3 * y**2 and g(x,y) = x**2 + y**2 - 4. Solution: We will solve this problem by performing the following steps: Specify the Lagrangian function for the problem Determine the K...

Detailed instructions on getting scenekit set up or installed.

public static IWebDriver dismissAlert(this IWebDriver driver) { try { IAlert alert = driver.SwitchTo().Alert(); alert.Dismiss(); } catch {} return driver; } public static IWebDriver acceptAlert(this IWebDriver driver) { try { IAlert a...

public static Screenshot TakeScreenshot(this IWebDriver _driver) { return ((ITakesScreenshot)_driver).GetScreenshot(); } Usage example: driver.TakeScreenshot().SaveAsFile(@"/Test/Test.png",ImageFormat.Png);

Dynamic queries are SET @sql = N'SELECT COUNT(*) FROM AppUsers WHERE Username = ''' + @user + ''' AND Password = ''' + @pass + '''' EXEC(@sql) If value of user variable is myusername'' OR 1=1 -- the following query will be executed: SELECT COUNT(*) FROM AppUsers WHERE Username = 'myusername...

from scipy.stats import rv_continuous import numpy class Neg_exp(rv_continuous): def _cdf(self, x, lamda): return 1-numpy.exp(-lamda*x) neg_exp = Neg_exp(name="Negative exponential", a=0) print (neg_exp.pdf(0,.5)) print (neg_exp.pdf(5,.5)) print (neg_exp.cdf(5...

There are many reasons a write operation may fail. A frequent one is because your security rules reject the operation, for example because you're not authenticated (by default a database can only be accessed by an authenticated user). You can see these security rule violations in the output of your...

SQL Server 2008 The ROW_NUMBER function can assign an incrementing number to each row in a result set. Combined with a Common Table Expression that uses a BETWEEN operator, it is possible to create 'pages' of result sets. For example: page one containing results 1-10, page two containing results 11...

SQL Server 2012 The OFFSET FETCH clause implements pagination in a more concise manner. With it, it's possible to skip N1 rows (specified in OFFSET) and return the next N2 rows (specified in FETCH): SELECT * FROM sys.objects ORDER BY object_id OFFSET 40 ROWS FETCH NEXT 10 ROWS ONLY The ORDER...

In earlier versions of SQL Server, developers had to use double sorting combined with the TOP keyword to return rows in a page: SELECT TOP 10 * FROM ( SELECT TOP 50 object_id, name, type, create_date FROM sys.objects ORDER BY name ASC ) AS data ...

Recommended way to install Slim framework is by using composer. Create an empty directory This directory will contain all required files for our Slim application to run. We call this directory root directory so we can address all other application files and directories relative to root directo...

ContactManager contactManager = Factory.CreateObject("tracking/contactManager", true) as ContactManager; Contact contact = contactManager.LoadContactReadOnly(userName); return contact;

This method doesn't require initialization of the tracker, which is handy if the state should be changed outside of the site context (for example in the shell). var stateManager = AutomationStateManager.Create(contact); automationStateManager.MoveToEngagementState(stateItem.ParentID, stateId); st...

When you use UNION operator on two query results, Query optimizer (QO) can use following operators to create a union of two result sets: Merge (Union) Concat (Union) Hash Match (Union) You can explicitly specify what operator should be used using OPTION() hint: select OrderID, OrderDate, Ex...

Specifies the max degree of parallelism for the query specifying this option. SELECT OrderID, AVG(Quantity) FROM Sales.OrderLines GROUP BY OrderID OPTION (MAXDOP 2); This option overrides the MAXDOP configuration option of sp_configure and Resource Governor. If MAXDOP is set to zero then...

By using the method GET_SUBMATCH of class CL_ABAP_MATCHER, we can get the data in the groups/subgroups. Goal: get the token to the right of the keyword 'Type'. DATA: lv_pattern TYPE string VALUE 'type\s+(\w+)', lv_test TYPE string VALUE 'data lwa type mara'. CREATE OBJECT ref_regex EX...