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Python 3.x3.3 Use yield from if you want to yield all values from another iterable: def foob(x): yield from range(x * 2) yield from range(2) list(foob(5)) # [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1] This works with generators as well. def fibto(n): a, b = 1, 1 while True: ...

One might want to group their data by the runs of a variable and perform some sort of analysis. Consider the following simple dataset: (dat <- data.frame(x = c(1, 1, 2, 2, 2, 1), y = 1:6)) # x y # 1 1 1 # 2 1 2 # 3 2 3 # 4 2 4 # 5 2 5 # 6 1 6 The variable x has three runs: a run of l...

Given this setup code: var dict = new Dictionary<int, string>() { { 1, "First" }, { 2, "Second" }, { 3, "Third" } }; You may want to read the value for the entry with key 1. If key doesn't exist getting a value will throw KeyNotFoundException,...

.reverse is used to reverse the order of items inside an array. Example for .reverse: [1, 2, 3, 4].reverse(); Results in: [4, 3, 2, 1] Note: Please note that .reverse(Array.prototype.reverse) will reverse the array in place. Instead of returning a reversed copy, it will return the same ar...

5.0 In PowerShell 5.0+ you can list available constructors by calling the static new-method without parentheses. PS> [DateTime]::new OverloadDefinitions ------------------- datetime new(long ticks) datetime new(long ticks, System.DateTimeKind kind) datetime new(int year, int month, int d...

Reading a file line by line public class Main { public static void main(String[] args) { try { Scanner scanner = new Scanner(new File("example.txt")); while(scanner.hasNextLine()) { String line = scanner.nextLine(); ...

The data.table package provides a convenient way to group by runs in data. Consider the following example data: library(data.table) (DT <- data.table(x = c(1, 1, 2, 2, 2, 1), y = 1:6)) # x y # 1: 1 1 # 2: 1 2 # 3: 2 3 # 4: 2 4 # 5: 2 5 # 6: 1 6 The variable x has three runs: a run ...

DT[where, select|update|do, by] syntax is used to work with columns of a data.table. The "where" part is the i argument The "select|update|do" part is the j argument These two arguments are usually passed by position instead of by name. Our example data below is mtcars =...

First install the .NET Core SDK by going through the installation instructions for the platform of your choice: Windows OSX Linux Docker After the installation has completed, open a command prompt, or terminal window. Create a new directory with mkdir hello_world and change into the ne...

At its simplest, a property is a function which returns a Bool. prop_reverseDoesNotChangeLength xs = length (reverse xs) == length xs A property declares a high-level invariant of a program. The QuickCheck test runner will evaluate the function with 100 random inputs and check that the result is...

You can use an instance of an object to form your parameters public class SearchParameters { public string SearchString { get; set; } public int Page { get; set; } } var template= new SearchParameters { SearchString = "Dapper", Page = 1 }; var p = new DynamicParameters...

# test date-time object options(digits.secs = 3) d = as.POSIXct("2016-08-30 14:18:30.58", tz = "UTC") format(d,"%S") # 00-61 Second as integer ## [1] "30" format(d,"%OS") # 00-60.99… Second as fractional ## [1] "30.579" for...

The quickCheck function tests a property on 100 random inputs. ghci> quickCheck prop_reverseDoesNotChangeLength +++ OK, passed 100 tests. If a property fails for some input, quickCheck prints out a counterexample. prop_reverseIsAlwaysEmpty xs = reverse xs == [] -- plainly not true for all ...

quickCheckAll is a Template Haskell helper which finds all the definitions in the current file whose name begins with prop_ and tests them. {-# LANGUAGE TemplateHaskell #-} import Test.QuickCheck (quickCheckAll) import Data.List (sort) idempotent :: Eq a => (a -> a) -> a -> Bool ...

fn main() { let maybe_cake = Some("Chocolate cake"); let not_cake = None; // The unwrap method retrieves the value from the Option // and panics if the value is None println!("{}", maybe_cake.unwrap()); // The expect method works much like the un...

What is a node.js module (link to article): A module encapsulates related code into a single unit of code. When creating a module, this can be interpreted as moving all related functions into a file. Now lets see an example. Imagine all files are in same directory: File: printer.js "use...

Fixnum#to_s takes an optional base argument and represents the given number in that base: 2.to_s(2) # => "10" 3.to_s(2) # => "11" 3.to_s(3) # => "10" 10.to_s(16) # => "a" If no argument is provided, then it represents the number in bas...

% Define serial port with a baud rate of 115200 rate = 115200; if ispc s = serial('COM1', 'BaudRate',rate); elseif ismac % Note that on OSX the serial device is uniquely enumerated. You will % have to look at /dev/tty.* to discover the exact signature of your % serial device ...

Assuming you created the serial port object s as in this example, then to close it fclose(s) However, sometimes you can accidentally lose the port (e.g. clear, overwrite, change scope, etc...), and fclose(s) will no longer work. The solution is easy fclose(instrfindall) More info at instrfin...

// View to hold the CAGradientLayer. let view: UIView = UIView(frame: CGRect(x: 0, y: 0, width: 320, height: 320)) // Initialize gradient layer. let gradientLayer: CAGradientLayer = CAGradientLayer() // Set frame of gradient layer. gradientLayer.frame = view.bounds // Color at...