Tutorial by Examples: dis

import cv2 image_path= #put your image path here #use imread() function to read image data to variable img. img = cv2.imread(image_path) #display image data in a new window with title 'I am an image display window' cv2.imshow('I am an image display window',img) #wait until user hi...

If you want PHP to display runtime errors on the page, you have to enable display_errors, either in the php.ini or using the ini_set function. You can choose which errors to display, with the error_reporting (or in the ini) function, which accepts E_* constants, combined using bitwise operators. P...

You can define a private rules to disable read and write access to your database by users. With these rules, you can only access the database when you have administrative privileges (which you can get by accessing the database through the Firebase console or by signing in from a server). // These...

If you have one of the supported Linux distributions, you can follow the steps on the .NET Core website: https://www.microsoft.com/net If you have an unsupported distribution: Download the .NET Core SDK from the links, picking the distribution closer to the used one. https://www.microsoft.com/net...

If you are optimizing all images manually, disable APT Cruncher for a smaller APK file size. android { aaptOptions { cruncherEnabled = false } }

Some teams find that they want to leave console log statements in their code, but not have them display in production. They will override the logging functions if a variable isn't set (possibly an environment variable). Additionally, this may qualify as a security feature in some situations. if (...

SELECT DISTINCT ContinentCode FROM Countries; This query will return all DISTINCT (unique, different) values from ContinentCode column from Countries table ContinentCodeOCEUASNAAF SQLFiddle Demo

If you want to remove duplicates from a result, you can use .distinct(): Customers.select(:country).distinct This queries the database as follows: SELECT DISTINCT "customers"."country" FROM "customers" .uniq() has the same effect. With Rails 5.0 it got deprecate...

Like any other java program, every swing program starts with a main method. The main method is initiated by the main thread. However, Swing components need to be created and updated on the event dispatch thread (or short: EDT). To illustrate the dynamic between the main thread and the EDT take a loo...

We can easily separate distribution specific tasks and variables into different dedicated .yml files. Ansible helps us to automatically identify the target hosts distribution via {{ ansible_distribution }} and {{ ansible_distribution_version }}, so we just have to name the distribution dedicated .y...

Setup your view controller to manage editing of text for the text field. class MyViewController: UITextFieldDelegate { override viewDidLoad() { super.viewDidLoad() textField.delegate = self } } textFieldShouldReturn is called every time the return butto...

Derives from Object Key members public Dispatcher Dispatcher { get; } Summary Most objects in WPF derive from DispatcherObject, which provides the basic constructs for dealing with concurrency and threading. Such objects are associated with a Dispatcher. Only the thread that the Dispatcher w...

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...

DataTables has the capability to enable or disable a number of its features, such as paging or searching. To choose these options, simply select them in your initialization: $(document).ready(function() { $('#tableid').DataTable( { "paging": false, //Turn off paging, all r...

gitk path/to/myfile

Let's say you have two commits d9e1db9 and 5651067 and want to see what happened between them. d9e1db9 is the oldest ancestor and 5651067 is the final descendant in the chain of commits. gitk --ancestry-path d9e1db9 5651067

If you have the version tag v2.3 you can display all commits since that tag. gitk v2.3..

To load an image and place it on the canvas var image = new Image(); // see note on creating an image image.src = "imageURL"; image.onload = function(){ ctx.drawImage(this,0,0); } Creating an image There are several ways to create an image new Image() document.createEleme...

On desktop apps, you may want to disable scroll-bounce, to give your app a more native feel. You can do this with javascript, by disabling how the browser controls the DOM: // prevent scrolling on the whole page // this is not meteorish; TODO: translate to meteor-centric code document.ontouchmove...

db.posts.find().forEach(function(doc){ if(doc.foo === 'bar'){ db.posts.remove({_id: doc._id}); } });