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How to write a query to get all departments where average age of employees making less than or $70000 is greather than or equal to 35? In order to that we need to write a query to match employees that have a salary that is less than or equal to $70000. Then add the aggregate stage to group the empl...

Consider the following example: public class Example { public int a, b, c, d; public void doIt() { a = b + 1; c = d + 1; } } If this class is used is a single-threaded application, then the observable behavior will be exactly as you would expect. For instan...

Convert from wide form to long form Load data USArrests from datasets. data("USArrests") head(USArrests) Murder Assault UrbanPop Rape Alabama 13.2 236 58 21.2 Alaska 10.0 263 48 44.5 Arizona 8.1 294 80 31.0 Arkansas 8...

Convert from long form to wide form To recover data from the previous example, use dcast like so. DTc <- dcast(DTmu, State + UrbanPop ~ Crime) This gives the data in the original wide form. State UrbanPop Murder Assault Rape 1: Alabama 58 13.2 236 21.2 2:...

Here is a basic class documentation example: /// Class description class Student { // Member description var name: String /// Method description /// /// - parameter content: parameter description /// /// - returns: return value description func say...

SAML specifies three key roles: The Identity Provider (IdP) The party which provides and maintains the identity of the users. This can be a directory service like ADFS or a custom database solution. The Service Provider (SP) The Service Provider is the actual service which the user tries...

@at-root directive can be used to localize variables. $color: blue; @at-root { $color: red; .a { color: $color; } .b { color: $color; } } .c { color: $color; } is compiled to: .a { color: red; } .b { color: red; } .c { color: blue; }

Define the variables within a formula field: Shared NumberVar x := 1000; Shared NumberVar y; Assigning the values is optional. To display the variable in a second formula later on in the report, the call is nearly identical: Shared NumberVar x; x

Custom matchers can be added in jasmine using the syntax: jasmine.addMatchers([ toMatch: function () { return { compare: function (actual, expected) { return { pass: actual===expected, message: "Expected actual to match expected...

Custom matchers will have their pass value negated when using 'not'. Custom matchers can have a negative compare attribute to explicitly handle cases where their negation is desired: toMatch: function () { return { compare: function (actual, expected) { return...

Time complexity is a property of Problems someone might want to solve computationally, Algorithms designed to solve such problems and Programs implementing such algorithms. An abstract concept requires no installation or setup. Simply take any problem, algorithm, or code and ask "How lo...

Many real-world database tables have many rows with DATETIME OR TIMESTAMP column values spanning a lot of time, including years or even decades. Often it's necessary to use a WHERE clause to retrieve some subset of that timespan. For example, we might want to retrieve rows for the date 1-September-2...

There is a dozen implementations of Standard ML. MLton produces very optimized code, but has no REPL. SML/NJ is the most widely used, but has slightly difficult error messages for learning purposes. Moscow ML and Poly/ML are easy to get started with, but don't support the .mlb package format. That i...

// Set up Express var express = require('express'); var app = express(); // Specify mount path, '/static', for the static directory app.use('/static', express.static('public')); // Start Express server app.listen(3030);

// Set up Express var express = require('express'); var app = express(); // Serve files from the absolute path of the directory app.use(express.static(__dirname + '/public')); // Start Express server app.listen(3030);

// Set up Express var express = require('express'); var app = express(); /* Serve from the absolute path of the directory that you want to serve with a */ virtual path prefix app.use('/static', express.static(__dirname + '/public')); // Start Express server app.listen(3030);

A lot of example code posted on StackOverflow includes snippets like this: if ("A".equals(someString)) { // do something } This does "prevent" or "avoid" a possible NullPointerException in the case that someString is null. Furthermore, it is arguable that ...

Detailed instructions on getting phonegap-build set up or installed.

Overview Android Studio's built-in update mechanism can be set to receive updates through any one of these four channels: Canary: Bleeding edge, released about weekly. These are early previews released in order to obtain real-world feedback during development. The canary channel will always have...

Detailed instructions on getting retrofit set up or installed.