nickleeh

val fibs: Stream[Int] = 0 #:: fibs.scanLeft(1)(_ + _)
fibs.take(20).toList
fibs take 20 toList

val fibs: Stream[BigInt] = 0 #:: fibs.scanLeft(1)(_ + _)

nickleeh

// Sequence of random numbers
open System

let randomSequence = 
    seq { 
    let rng = new Random()
    while true do
        yield rng.Next()
    }
    

nickleeh

open System.Collections.Generic
let memoize (f : 'a -> 'b) =
let dict = new Dictionary<'a, 'b>()
let memoizedFunc (input : 'a) =
match dict.TryGetValue(input) with
| true, x -> x
| false, _ ->
// Evaluate and add to lookup table
let answer = f input
dict.Add(input, answer)

nickleeh

// Example 7-20. Memoization of recursive functions
> // WRONG way to memoize the function - fib doesn't call the
// memoized version recursively.
let wrongMemFib =
let rec fib x =
match x with
| 0 | 1 -> 1
| 2 -> 2
| n -> fib (n - 1) + fib (n - 2)
memoize fib;;

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let toBigInt (n: int) = bigint(n)
let fac n = 
    [1..n] 
    |> List.map toBigInt 
    |> List.reduce (*) 

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type Duck () = 
    member this.sayQuack = printfn "quack, quack..."

type Bird () = 
    member this.sayQuack = printfn "tweet, tweet..."

type Dog () =
    member this.bark = printfn "woof, woof..."

let duck = Duck()

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library(matlab)

as.logical(isprime(7))
as.logical(isprime(42))

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randNorm <- rnorm(3000)
randDensity <- dnorm(randNorm)
require(ggplot2)
ggplot(data.frame(x = randNorm, y = randDensity)) + aes(x = x, y = y) + geom_point() + labs(x = "Random Normal Variables", y = "Density")

nickleeh

Libraries

• jQuery - The de-facto library for the modern age. It makes things like HTML document traversal and manipulation, event handling, animation, and Ajax much simpler with an easy-to-use API that works across a multitude of browsers.
• Backbone - Backbone.js gives structure to web applications by providing models with key-value binding and custom events, collections with a rich API of enumerable functions, views with declarative event handling, and connects it all to your existing API over a RESTful JSON interface.
• AngularJS - Conventions based MVC framework for HTML5 apps.
• Underscore - Underscore is a utility-belt library for JavaScript that provides a lot of the functional programming support that you would expect in Prototype.js (or Ruby), but without extending any of the built-in JavaScript objects.
• lawnchair - Key/value store adapter for indexdb, localStorage

nickleeh

// Use Gists to store code you would like to remember later on
console.log(window); // log the "window" object to the console