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Define AccumulatorParam import org.apache.spark.AccumulatorParam object StringAccumulator extends AccumulatorParam[String] { def zero(s: String): String = s def addInPlace(s1: String, s2: String)= s1 + s2 } Use: val accumulator = sc.accumulator("")(StringAccumulator) sc.pa...

Define AccumulatorParam: from pyspark import AccumulatorParam class StringAccumulator(AccumulatorParam): def zero(self, s): return s def addInPlace(self, s1, s2): return s1 + s2 accumulator = sc.accumulator("", StringAccumulator()) def add(x): gl...

AlertDialog.Builder builder = new AlertDialog.Builder(context); //Set Title builder.setTitle("Reset...") //Set Message .setMessage("Are you sure?") //Set the icon of the dialog .setIcon(drawable) //Set...

Let there be Activity B that can be opened, and can further start more Activities. But, user should not encounter it when navigating back in task activities. The simplest solution is to set the attribute noHistory to true for that <activity> tag in AndroidManifest.xml: <activity a...

Imagine you have the following HTML: <div> <label>Name:</label> John Smith </div> And you need to locate the text "John Smith" after the label element. In this case, you can locate the label element by text and then use .next_sibling property: from ...

BeautifulSoup has a limited support for CSS selectors, but covers most commonly used ones. Use select() method to find multiple elements and select_one() to find a single element. Basic example: from bs4 import BeautifulSoup data = """ <ul> <li class="item&quo...

When the destructor for std::thread is invoked, a call to either join() or detach() must have been made. If a thread has not been joined or detached, then by default std::terminate will be called. Using RAII, this is generally simple enough to accomplish: class thread_joiner { public: thre...

Leading Zeros let number: Int = 7 let str1 = String(format: "%03d", number) // 007 let str2 = String(format: "%05d", number) // 00007 Numbers after Decimal let number: Float = 3.14159 let str1 = String(format: "%.2f", number) // 3.14 let str2 = String(format: &...

This example was done in order to demonstrate how you can perform a deep filter in a child array without the necessity of a custom filter. Controller: (function() { "use strict"; angular .module('app', []) .controller('mainCtrl', mainCtrl); function mainCtrl() { ...

Download a distributed archive from Binaries section of JMeter from Download Apache JMeter page. Depending on the version you downloaded, check minimal Java version requirements and install Java if needed. Ensure the JAVA_HOME environment variable is set and points to a correct version. ...

Installing Wildfly is just a matter of unzipping the distribution into your local machine. Wildfly can be dowloaded from its official website. Once it is unzipped go in to bin directory of installation and run standalone.sh for Linux systems or standalone.bat for Windows systems to start your WildF...

demoApp.directive('demoDirective', function () { var directiveDefinitionObject = { multiElement: priority: terminal: scope: {}, bindToController: {}, controller: controllerAs: require: restrict: templateNamespace: template: templateU...

.SD .SD refers to the subset of the data.table for each group, excluding all columns used in by. .SD along with lapply can be used to apply any function to multiple columns by group in a data.table We will continue using the same built-in dataset, mtcars: mtcars = data.table(mtcars) # Let's not ...

SyncAdapter /** * Define a sync adapter for the app. * <p/> * <p>This class is instantiated in {@link SyncService}, which also binds SyncAdapter to the system. * SyncAdapter should only be initialized in SyncService, never anywhere else. * <p/> * <p>The system ca...

Validating array form input fields is very simple. Suppose you have to validate each name, email and father name in a given array. You could do the following: $validator = \Validator::make($request->all(), [ 'name.*' => 'required', 'email.*' => 'email|unique:users'...

Sometimes it is appropriate to use an immutable empty collection. The Collections class provides methods to get such collections in an efficient way: List<String> anEmptyList = Collections.emptyList(); Map<Integer, Date> anEmptyMap = Collections.emptyMap(); Set<Number> anEmptySe...

In Julia, the @show macro is often useful for debugging purposes. It displays both the expression to be evaluated and its result, finally returning the value of the result: julia> @show 1 + 1 1 + 1 = 2 2 It is straightforward to create our own version of @show: julia> macro myshow(exp...

Partial credit to this SO answer. List Concatenation aggregates a column or expression by combining the values into a single string for each group. A string to delimit each value (either blank or a comma when omitted) and the order of the values in the result can be specified. While it is not part ...

Sometimes you want to add an element to the beginning of an array without modifying any of the current elements (order) within the array. Whenever this is the case, you can use array_unshift(). array_unshift() prepends passed elements to the front of the array. Note that the list of elements is ...

When running from the CLI, PHP exhibits some different behaviours than when run from a web server. These differences should be kept in mind, especially in the case where the same script might be run from both environments. No directory change When running a script from a web server, the current w...