Tutorial by Examples: st

This example sorts elements in ascending order of a key using a map. You can use any type, including class, instead of std::string, in the example below. #include <iostream> #include <utility> #include <map> int main() { std::map<double, std::string> sorted_map; ...

db.people.getIndexes() This will return an array of documents each describing an index on the people collection

The Timeline object allows you to get the execution time for each node in the graph: you use a classic sess.run() but also specify the optional arguments options and run_metadata you then create a Timeline object with the run_metadata.step_stats data Here is an example program that measures...

To make a script to replace a phrase use the ::abbreviation:: hotstring syntax. It will replace btw with by the way whenever you enter btw and then the space key. ::btw::by the way If you wanted to make a login script to make logging in faster you could make a script like this (the file is not e...

Create your RecyclerView in your layout xml file: <android.support.v7.widget.RecyclerView android:id="@+id/recycleView" android:layout_width="match_parent" android:layout_height="match_parent" /> Create your Model...

When should I use it When the code inside an inline listener is too big and your method / class becomes ugly and hard to read You want to perform same action in various elements (view) of your app To achieve this you need to create a class implementing one of the listeners in the View API. ...

There are two ways to setup the Apache Flex SDK. You can use the provided Apache Flex SDK Installer, an Adobe AIR application that automates the process (on Windows or OS X/macOS). Or you can install it manually which obviously requires a greater comfort with your platform but provides more flexibi...

String templates are a convenient way of mixing literal strings with values from variables: WRITE |Hello, { lv_name }, nice to meet you!|. It can also format things like dates. To use the logged on user's date format: WRITE |The order was completed on { lv_date DATE = USER } and can not be chan...

Suppose we have the following XAML snippet: <ListBox x:Name="MyListBox" /> Then in the code-behind for this XAML file, we write the following in the constructor: MyListBox.ItemsSource = new[] { 1, 2, 3, 4, 5 }; Running the application, we get a list of numbers we enter...

Modify your Gemfile to include the Devise gem: gem 'devise' Then update your gems with: $ bundle install Run the installers in your project: $ rails generate devise:install Then create your Devise model (e.g. User) with: $ rails generate devise User you'll need to set up the default ...

The System.Web.SessionState.HttpSessionState object provides a way to persist values between HTTP requests. In the example below, a user's preference for warnings is being saved in the session. Later on, while serving another request to the user, the application can read this preference from session...

If you find that you have multiple servers that need to share session state, storing it in the ASP.NET process memory will not work. For example you may deploy into a web-farm environment with a load balancer that distributes requests in a round-robin fashion. In this environment a single user's req...

If you don't want to use SQL server you can use Amazon's hosted Dynamo DB nosql database as a session store. You'll need the AWS SDK. To install this from the Visual Studio nuget package manager console use the following command Install-Package AWSSDK You can then configure your sessionState p...

When one wishes to convert a list to a vector or data.frame object empty elements are typically dropped. This can be problematic which a list is created of a desired length are created with some empty values (e.g. a list with n elements is created to be added to an m x n matrix, data.frame, or data...

user_one = User.find(1) user_two = User.find(1) user_one.name = "John" user_one.save # Run at the same instance user_two.name = "Doe" user_two.save # Raises a ActiveRecord::StaleObjectError

appointment = Appointment.find(5) appointment.lock! #no other users can read this appointment, #they have to wait until the lock is released appointment.save! #lock is released, other users can read this account

If you want to use RSpec for a Rails project, you should use the rspec-rails gem, which can generate helpers and spec files for you automatically (for example, when you create models, resources or scaffolds using rails generate). Add rspec-rails to both the :development and :test groups in the Gem...

To work with ConstraintLayout, you need Android Studio Version 2.2 or newer and have at least version 32 (or higher) of Android Support Repository. Add the Constraint Layout library as a dependency in your build.gradle file: dependencies { compile 'com.android.support.constraint:constraint...

Example of calling an extension method as an extension and as a regular method. public Class MyClass Sub Main() 'Extension called directly on the object. Dim Version = Assembly.GetExecutingAssembly.GetVersionFromAssembly() 'Called as a regular method. ...

A common problem in code that uses multidimensional arrays, arrays of pointers, etc. is the fact that Type** and Type[M][N] are fundamentally different types: #include <stdio.h> void print_strings(char **strings, size_t n) { size_t i; for (i = 0; i < n; i++) puts(str...