Tutorial by Examples: v

In following example we will create table movies with AWS Ruby SDK v2. Here, each Movie as one unique Partition Key as id, and Range Key year. Apart from this we want to be able to query movies with their name, hence we will create a Global Secondary Index (GSI) name-year-index with name as Hash Ke...

Fugitive Vim is a plugin by Tim Pope that provides access to git commands that you can execute without leaving vim. Some common commands include: :Gedit - edit a file in the index and write it to stage the the changes :Gstatus - equivalent of git status :Gblame - brings up vertical split of outp...

set var to 2 if var = 2 then say "Var equals 2" end if

set var1 to 5 //set the number to anything if var1 = 5 then say "Var one equals 5" else say "Var one does not equal 5" end if

Any @Component or @Configuration could be marked with @Profile annotation @Configuration @Profile("production") public class ProductionConfiguration { // ... } The same in XML config <beans profile="dev"> <bean id="dataSource" class="&l...

Suppose you need to work on three different projects project A, project B and project C. project A and project B need python 3 and some required libraries. But for project C you need python 2.7 and dependent libraries. So best practice for this is to separate those project environments. To create v...

Angular 4 is now available! Actually Angular uses semver since Angular 2, which requires the major number being increased when breaking changes were introduced. The Angular team postponed features that cause breaking changes, which will be released with Angular 4. Angular 3 was skipped to be able to...

Suppose you need to work on three different projects project A, project B and project C. project A and project B need python 3 and some required libraries. But for project C you need python 2.7 and dependent libraries. So best practice for this is to separate those project environments. For creati...

class ConversationsTableViewController: UITableViewController, NSFetchedResultsControllerDelegate { private var fetchedResultsController: NSFetchedResultsController<Conversation>! override func viewDidLoad() { super.viewDidLoad() initializeFetchedResultsController() } private...

Supervised learning is a type of machine learning algorithm that uses a known data-set (called the training data-set) to make predictions. Category of supervised learning: Regression: In a regression problem, we are trying to predict results within a continuous output, meaning that we are trying...

Unsupervised learning allows us to approach problems with little or no idea what our results should look like. We can derive structure from data where we don't necessarily know the effect of the variables. Example: Clustering: Is used for exploratory data analysis to find hidden patterns or groupi...

To get started, create a new Maven webapp (how to do this is outside the scope of this example). In your pom.xml, add the following two dependencies <dependency> <groupId>org.glassfish.jersey.containers</groupId> <artifactId>jersey-container-servlet</artifactId&...

Calendar : Key : Privacy - Calendars Usage Description Value : $(PRODUCT_NAME) calendar events Reminder : Key : Privacy - Reminders Usage Description Value : $(PRODUCT_NAME) reminder use Contact : Key : Privacy - Contacts Usage Description Value : $(PRODUCT_...

In DRF, serializer validation is run in a specific, undocumented order Field deserialization called (serializer.to_internal_value and field.run_validators) serializer.validate_[field] is called for each field. Serializer-level validators are called (serializer.run_validation followed by seriali...

public class Foobar { public static void main(String[] args) { // example: Boolean ignore = null; if (ignore == false) { System.out.println("Do not ignore!"); } } } The pitfall here is that null is compared to false. Since w...

In this example we are going to create a view. A view is mostly used as a simple way of fetching data from multiple tables. Example 1: View with a select on one table. CREATE OR REPLACE VIEW LessonView AS SELECT L.* FROM Lesson L; Example 2: View with a select o...

Parameter TypesReturn TypeInterface()voidRunnable()TSupplier()booleanBooleanSupplier()intIntSupplier()longLongSupplier()doubleDoubleSupplier(T)voidConsumer<T>(T)TUnaryOperator<T>(T)RFunction<T,R>(T)booleanPredicate<T>(T)intToIntFunction<T>(T)longToLongFunction<T>(...

You can define a function to be recursive with the rec keyword, so it can call itself. # let rec fact n = match n with | 0 -> 1 | n -> n * fact (n - 1);; val fact : int -> int = <fun> # fact 0;; - : int = 1 # fact 4;; - : int = 24 You can also define mutually re...

General Imports, using jinja2 to populate templates into htmls. import jinja2 import webapp2 Important import to use Users API: from google.appengine.api import users Setting of Jinja environment: [into the example the tehcnology selected to populate the information into the frontend] JINJ...

Suppose we have a POJO class User we need to validate. public class User { @NotEmpty @Size(min=5) @Email private String email; } and a controller method to validate the user instance public String registerUser(@Valid User user, BindingResult result); Let's extend the U...