Tutorial by Examples: r

For creating your first project in Phoenix framework at this point you should have, Elixir, Erlang, Hex, and the Phoenix archive installed. You should also have PostgreSQL and node.js installed to build a default application. Open terminal or command prompt and go to location on your file system wh...

1..100 | ForEach-Object { Write-Progress -Activity "Copying files" -Status "$_ %" -Id 1 -PercentComplete $_ -CurrentOperation "Copying file file_name_$_.txt" Start-Sleep -Milliseconds 500 # sleep simulates working code, replace this line with your e...

1..10 | foreach-object { $fileName = "file_name_$_.txt" Write-Progress -Activity "Copying files" -Status "$($_*10) %" -Id 1 -PercentComplete ($_*10) -CurrentOperation "Copying file $fileName" 1..100 | foreach-object { ...

The simplest way to understand creating and modifying SVG elements is to operate on the elements using the DOM Level 2 Core interfaces, as you would with HTML or XML. It is imperative that the elements created from JavaScript are created in the same namespace declared in the SVG element - in this e...

You can use either DOM Level 2 Core methods getAttribute(), getAttributeNS(), setAttribute(), and setAttributeNS() to read and write values from SVG elements, or you can use custom properties and methods specified in the SVG 1.1 IDL (Interface Definition Language). Simple Numeric Attributes For ex...

Using the mouse to drag an SVG element (or group of elements) can be accomplished by: Adding mousedown handler to starts the drag: adding a translation on the element to use during dragging (if needed), tracking mousemove events, and adding a mouseup handler to end the drag. During mousemove, tr...

QThread is a handle to a platform thread. It lets you manage the thread by monitoring its lifetime, and requesting that it finishes its work. In most cases inhering from the class is not recommended. The default run method starts an event loop that can dispatch events to objects living in the class...

# Set The Formatting $xmlsettings = New-Object System.Xml.XmlWriterSettings $xmlsettings.Indent = $true $xmlsettings.IndentChars = " " # Set the File Name Create The Document $XmlWriter = [System.XML.XmlWriter]::Create("C:\YourXML.xml", $xmlsettings) # Write the XML ...

@supports (display: flex) { /* Flexbox is available, so use it */ .my-container { display: flex; } } In terms of syntax, @supports is very similar to @media, but instead of detecting screen size and orientation, @supports will detect whether the browser can handle a given CSS rule....

To detect multiple features at once, use the and operator. @supports (transform: translateZ(1px)) and (transform-style: preserve-3d) and (perspective: 1px) { /* Probably do some fancy 3d stuff here */ } There is also an or operator and a not operator: @supports (display: flex) or (display...

config.paths.html represents the path to your HTML file. gulp.task("watch", function() { gulp.watch(config.paths.html, ["html"]); }); The task should be added to default as well: gulp.task("default", ["html", "watch"]);

Build: xcodebuild -exportArchive -exportFormat ipa \ -archivePath "/Users/username/Desktop/MyiOSApp.xcarchive" \ -exportPath "/Users/username/Desktop/MyiOSApp.ipa" \ -exportProvisioningProfile "MyCompany Distribution Profile" Archive: xcodebuild -pro...

To consume a REST API with RestTemplate, create a Spring boot project with the Spring boot initialzr and make sure the Web dependency is added: <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dep...

ActiveRecord includes default_scope, to automatically scope a model by default. class Post default_scope ->{ where(published: true).order(created_at: :desc) } end The above code will serve posts which are already published when you perform any query on the model. Post.all # will only lis...

The qsort() standard library function is a good example of how one can use void pointers to make a single function operate on a large variety of different types. void qsort ( void *base, /* Array to be sorted */ size_t num, /...

JSON_VALUE function enables you to take a data from JSON text on the path specified as the second argument, and use this value in any part of the select query: select ProductID, Name, Color, Size, Price, JSON_VALUE(Data, '$.Type') as Type from Product where JSON_VALUE(Data, '$.Type') = 'part' ...

Once JSON values are extracted from JSON text, you can use them ina any part of the query. You can create some kind of report on JSON data with grouping aggregations, etc: select JSON_VALUE(Data, '$.Type') as type, AVG( cast(JSON_VALUE(Data, '$.ManufacturingCost') as float) ) as cost from...

If some JSON text might not be properly formatted, you can remove those entries from query using ISJSON function. select ProductID, Name, Color, Size, Price, JSON_VALUE(Data, '$.Type') as Type from Product where JSON_VALUE(Data, '$.Type') = 'part' and ISJSON(Data) > 0

JSON_MODIFY function can be used to append new value to some array inside JSON: update Product set Data = JSON_MODIFY(Data, 'append $.tags', "sales") where ProductID = 17; New value will be appended at the end of the array, or a new array with value ["sales"] will be create...

If you have a "child table" formatted as JSON collection and stored in-row as JSON column, you can unpack this collection, transform it to table and join it with parent row. Instead of the standard JOIN operator, you should use CROSS APPLY. In this example, product parts are formatted as ...