Tutorial by Examples: e

Elements of the same class can often be concatenated into arrays (with a few rare exceptions, e.g. function handles). Numeric scalars, by default of class double, can be stored in a matrix. >> A = [1, -2, 3.14, 4/5, 5^6; pi, inf, 7/0, nan, log(0)] A = 1.0e+04 * 0.0001 -0.0002 0...

Detailed instructions on getting android-layout set up or installed.

The for and while compound statements (loops) can optionally have an else clause (in practice, this usage is fairly rare). The else clause only executes after a for loop terminates by iterating to completion, or after a while loop terminates by its conditional expression becoming false. for i in r...

To make a rounded UIView, specify a cornerRadius for the view's layer. This also applies any class which inherits from UIView, such as UIImageView. Programmatically Swift Code someImageView.layoutIfNeeded() someImageView.clipsToBounds = true someImageView.layer.cornerRadius = 10 Objective-C...

In this example, we will look at a method for returning the last non-empty row in a column for a data set. This method will work regardless of empty regions within the data set. However caution should be used if merged cells are involved, as the End method will be "stopped" against a mer...

Any Fortran program has to include end as last statement. Therefore, the simplest Fortran program looks like this: end Here are some examples of "hello, world" programs: print *, "Hello, world" end With write statement: write(*,*) "Hello, world" end For c...

The double-negation !! is not a distinct JavaScript operator nor a special syntax but rather just a sequence of two negations. It is used to convert the value of any type to its appropriate true or false Boolean value depending on whether it is truthy or falsy. !!1 // true !!0 ...

Another neat feature using slices is slice assignment. Python allows you to assign new slices to replace old slices of a list in a single operation. This means that if you have a list, you can replace multiple members in a single assignment: lst = [1, 2, 3] lst[1:3] = [4, 5] print(lst) # Out: [1...

Detailed instructions on getting Nativescript set up or installed. The following examples show the required steps to set up a Windows or OSX system and then sign post to troubleshooting guides in case you have any trouble. In addition, there are examples of how to set up recommended workflows, IDE...

Dart has If Else: if (year >= 2001) { print('21st century'); } else if (year >= 1901) { print('20th century'); } else { print('We Must Go Back!'); } Dart also has a ternary if operator: var foo = true; print(foo ? 'Foo' : 'Bar'); // Displays "Foo".

While loops and do while loops are allowed in Dart: while(peopleAreClapping()) { playSongs(); } and: do { processRequest(); } while(stillRunning()); Loops can be terminated using a break: while (true) { if (shutDownRequested()) break; processIncomingRequests(); } You can s...

Dart has a switch case which can be used instead of long if-else statements: var command = 'OPEN'; switch (command) { case 'CLOSED': executeClosed(); break; case 'OPEN': executeOpen(); break; case 'APPROVED': executeApproved(); break; case 'UNSURE': ...

To check for a precise number of elements in the collection def f(ints: Seq[Int]): String = ints match { case Seq() => "The Seq is empty !" case Seq(first) => s"The seq has exactly one element : $first" case Seq(first, second) => s"The...

All Java exceptions are instances of classes in the Exception class hierarchy. This can be represented as follows: java.lang.Throwable - This is the base class for all exception classes. Its methods and constructors implement a range of functionality common to all exceptions. java.lang.Excep...

$fruit1 = ['apples', 'pears']; $fruit2 = ['bananas', 'oranges']; $all_of_fruits = array_merge($fruit1, $fruit2); // now value of $all_of_fruits is [0 => 'apples', 1 => 'pears', 2 => 'bananas', 3 => 'oranges'] Note that array_merge will change numeric indexes, but overwrite string...

A Pseudo Distributed Cluster Setup Procedure Prerequisites Install JDK1.7 and set JAVA_HOME environment variable. Create a new user as "hadoop". useradd hadoop Setup password-less SSH login to its own account su - hadoop ssh-keygen << Press ENTER for all prompt...

x = (1, 2, 3) x[0] # 1 x[1] # 2 x[2] # 3 x[3] # IndexError: tuple index out of range Indexing with negative numbers will start from the last element as -1: x[-1] # 3 x[-2] # 2 x[-3] # 1 x[-4] # IndexError: tuple index out of range Indexing a range of elements print(x[:-1]) # (1,...

A context manager is an object that is notified when a context (a block of code) starts and ends. You commonly use one with the with statement. It takes care of the notifying. For example, file objects are context managers. When a context ends, the file object is closed automatically: open_file = ...

In Python 2, an iterator can be traversed by using a method called next on the iterator itself: Python 2.x2.3 g = (i for i in range(0, 3)) g.next() # Yields 0 g.next() # Yields 1 g.next() # Yields 2 In Python 3 the .next method has been renamed to .__next__, acknowledging its “magic” ro...

SELECT * FROM Employees ORDER BY LName This statement will return all the columns from the table Employees. IdFNameLNamePhoneNumber2JohnJohnson24681012141JamesSmith12345678903MichaelWilliams1357911131 SELECT * FROM Employees ORDER BY LName DESC Or SELECT * FROM Employees ORDER BY LName ASC...