Tutorial by Examples: io

Every function has its own function type, made up of the parameter types and the return type of the function itself. For example the following function: func sum(x: Int, y: Int) -> (result: Int) { return x + y } has a function type of: (Int, Int) -> (Int) Function types can thus be use...

Problem: When you use many labels inside a view, you maybe get a warning: How can we fix this warning? Solution: We calculate and set the priorities in order. The priorities must be different from labels. It means which is important will get higher priority. For example, in my case, I set the ve...

Step 1: In Xcode: File -> New -> File -> Resource -> GPX File -> Next -> Give the GPX file a name(It's Taipei in this example) -> Create Step 2: Edit the GPX file <?xml version="1.0"?> <gpx version="1.1" creator="Xcode"> <wpt ...

Often in R you'll want to know things about an object or variable you're working with. This can be useful when reading someone else's code or even your own, especially when using packages that are new to you. Suppose we create a variable a: a <- matrix(1:9, 3, 3) What data type is this? Yo...

a, b = 1, 2 import math math.sin(a) # returns the sine of 'a' in radians # Out: 0.8414709848078965 math.cosh(b) # returns the inverse hyperbolic cosine of 'b' in radians # Out: 3.7621956910836314 math.atan(math.pi) # returns the arc tangent of 'pi' in radians # Out: 1.2626272556789...

public function drawDisplayObjectUsingBounds(source:DisplayObject):BitmapData { var bitmapData:BitmapData;//declare a BitmapData var bounds:Rectangle = source.getBounds(source);//get the source object actual size //round bounds to integer pixel values (to aviod 1px str...

UIBezierPath using to create a circular path ShapeLayer CAShapeLayer *circleLayer = [CAShapeLayer layer]; [circleLayer setPath:[[UIBezierPath bezierPathWithOvalInRect: CGRectMake(50, 50, 100, 100)] CGPath]]; circleLayer.lineWidth = 2.0; [circleLayer setStrokeColor:[[UIColor redColor] CGColor]];...

Const baseString As String = "Hello World" Dim charLength As Long charLength = Len(baseString) 'charlength = 11

Const baseString As String = "Hello World" Dim byteLength As Long byteLength = LenB(baseString) 'byteLength = 22

The first step in accessing a data source via ADO is creating an ADO Connection object. This is typically done using a connection string to specify the data source parameters, although it is also possible to open a DSN connection by passing the DSN, user ID, and password to the .Open method. Note t...

ADO connections can be used to perform pretty much any database function that the provider supports via SQL. In this case it isn't always necessary to use the Recordset returned by the Execute function, although it can be useful for obtaining key assignments after INSERT statements with @@Identity o...

'Declare and assign a string array Dim widgetNames(2) As String widgetNames(0) = "foo" widgetNames(1) = "bar" widgetNames(2) = "fizz" 'Concatenate with Join and separate each element with a 3-character string concatenatedString = VBA.Strings.Join(widgetNames, &q...

Dim lineOfHyphens As String 'Assign a string with 80 repeated hyphens lineOfHyphens = String$(80, "-")

Dim stringOfSpaces As String 'Assign a string with 255 repeated spaces using Space$ stringOfSpaces = Space$(255) 'Assign a string with 255 repeated spaces using String$ stringOfSpaces = String$(255, " ")

The purpose of this example is to show how we can realize the Strategy pattern using Java 8 functional interfaces. We will start with a simple use case codes in classic Java, and then recode it in the Java 8 way. The example problem we using is a family of algorithms (strategies) that describe dif...

To generate documentation in HTML format from @doc and @moduledoc attributes in your source code, add ex_doc and a markdown processor, right now ExDoc supports Earmark, Pandoc, Hoedown and Cmark, as dependencies into your mix.exs file: # config/mix.exs def deps do [{:ex_doc, "~> 0.11&...

from datetime import timedelta from django.utils import timezone from psycopg2.extras import DateTimeTZRange # To create a "period" object we will use psycopg2's DateTimeTZRange # which takes the two datetime bounds as arguments period_start = timezone.now() period_end = period_s...

Use assert_raise to test if an exception was raised. assert_raise takes in an Exception and a function to be executed. test "invalid block size" do assert_raise(MerkleTree.ArgumentError, (fn() -> MerkleTree.new ["a", "b", "c"] end)) end Wrap a...

import Session Class use yii\web\Session; Create a session $session = Yii::$app->session; $session->open(); // open a session $session->close(); // close a session Store the value in session variable. $session = Yii::$app->session; $session->set('name', 'stack'); OR ...

Use defdelegate to define functions that delegate to functions of the same name defined in another module: defmodule Math do defdelegate pi, to: :math end iex> Math.pi 3.141592653589793