# HG changeset patch
# User fahadausaf <fahad.ausaf@icloud.com>
# Date 1414254536 -3600
# Node ID 197babb055393faedcee2a7c5593c2cc02bbdf33
# Parent  2345ba5b42648e2b80729a5f18fe6bd399306508
scala by example code

diff -r 2345ba5b4264 -r 197babb05539 Fahad/Scala/Chapter5.sc
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Fahad/Scala/Chapter5.sc	Sat Oct 25 17:28:56 2014 +0100
@@ -0,0 +1,55 @@
+package greeter
+
+object Chapter5 {
+  println("Welcome to the Scala worksheet")       //> Welcome to the Scala worksheet
+
+  /////////////////////////////////////////////////////////////////////////////
+  //   CHAPTER 5: FIRST-CLASS FUNCTIONS
+
+  /*
+  // Write a function to sumall integers between two given numbers a and b
+  def sumInts(a: Int, b: Int): Int =
+    if (a > b) 0 else a + sumInts(a + 1, b)
+
+  sumInts(1, 5)
+
+  //Write a function to sum the squares of all integers between two given numbers a and b
+  def square(x: Int): Int = x * x
+  def sumSquares(a: Int, b: Int): Int =
+    if (a > b) 0 else square(a) + sumSquares(a + 1, b)
+
+  square(5)
+
+  //Write a function to sum the powers 2n of all integers n between two given numbers a and b:
+  def powerOfTwo(x: Int): Int = if (x == 0) 1 else 2 * powerOfTwo(x - 1)
+  def sumPowersOfTwo(a: Int, b: Int): Int =
+    if (a > b) 0 else powerOfTwo(a) + sumPowersOfTwo(a + 1, b)
+
+  sumPowersOfTwo(2, 4)
+  */
+
+  def sum(f: Int => Int, a: Int, b: Int): Int =
+    if (a > b) 0 else f(a) + sum(f, a + 1, b)     //> sum: (f: Int => Int, a: Int, b: Int)Int
+
+  //def sumInts(a: Int, b: Int): Int = sum(id, a, b)
+  //def sumInts(a: Int, b: Int): Int = sum((x: Int) => x, a, b)
+  def sumInts(a: Int, b: Int): Int = sum(x => x, a, b)
+                                                  //> sumInts: (a: Int, b: Int)Int
+  //def sumSquares(a: Int, b: Int): Int = sum(square, a, b)
+  //def sumSquares(a: Int, b: Int): Int = sum((x: Int) => x * x, a, b)
+  def sumSquares(a: Int, b: Int): Int = sum(x => x * x, a, b)
+                                                  //> sumSquares: (a: Int, b: Int)Int
+  def sumPowersOfTwo(a: Int, b: Int): Int = sum(powerOfTwo, a, b)
+                                                  //> sumPowersOfTwo: (a: Int, b: Int)Int
+  
+  def id(x: Int): Int = x                         //> id: (x: Int)Int
+	def square(x: Int): Int = x * x           //> square: (x: Int)Int
+	def powerOfTwo(x: Int): Int = if (x == 0) 1 else 2 * powerOfTwo(x - 1)
+                                                  //> powerOfTwo: (x: Int)Int
+                                                  
+  // 5.2: Currying
+  
+  
+  
+  
+}
\ No newline at end of file
diff -r 2345ba5b4264 -r 197babb05539 Fahad/Scala/WorkSheet.sc
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Fahad/Scala/WorkSheet.sc	Sat Oct 25 17:28:56 2014 +0100
@@ -0,0 +1,81 @@
+package greeter
+
+object WorkSheet {
+  println("Welcome to the Scala worksheet")       //> Welcome to the Scala worksheet
+
+  val x = 5                                       //> x  : Int = 5
+  def increase(i: Int) = i + 1                    //> increase: (i: Int)Int
+  increase(x)                                     //> res0: Int = 6
+
+  // Expressions And Simple Functions
+
+  87 + 145                                        //> res1: Int(232) = 232
+  5 + 2 * 3                                       //> res2: Int = 11
+
+  "Hello" + " World!"                             //> res3: String("Hello World!") = Hello World!
+
+  def scale = 5                                   //> scale: => Int
+  7 * scale                                       //> res4: Int = 35
+
+  def pi = 3.141592653589793                      //> pi: => Double
+  def radius = 10                                 //> radius: => Int
+  2 * pi * radius                                 //> res5: Double = 62.83185307179586
+
+  // PARAMETERS
+
+  def square(x: Double) = x * x                   //> square: (x: Double)Double
+  square(2)                                       //> res6: Double = 4.0
+  square(square(4))                               //> res7: Double = 256.0
+
+  def sumOfSquares(x: Double, y: Double) = square(x) + square(y)
+                                                  //> sumOfSquares: (x: Double, y: Double)Double
+  sumOfSquares(3, 2 + 2)                          //> res8: Double = 25.0
+
+  def loop: Int = loop                            //> loop: => Int
+  def first(x: Int, y: Int) = x                   //> first: (x: Int, y: Int)Int
+  def constOne(x: Int, y: => Int) = 1             //> constOne: (x: Int, y: => Int)Int
+  constOne(1, loop)                               //> res9: Int = 1
+
+  // 4.3 CONDITIONAL EXPRESSIONS
+
+  def abs(x: Double) = if (x >= 5) x + 1 else x - 1
+                                                  //> abs: (x: Double)Double
+  abs(4)                                          //> res10: Double = 3.0
+
+  // 4.4: Square Roots by Newton's Method
+
+  def sqrtIter(guess: Double, x: Double): Double =
+    if (isGoodEnough(guess, x)) guess
+    else sqrtIter(improve(guess, x), x)           //> sqrtIter: (guess: Double, x: Double)Double
+
+  def improve(guess: Double, x: Double) =
+    (guess + x / guess) / 2                       //> improve: (guess: Double, x: Double)Double
+
+  def isGoodEnough(guess: Double, x: Double) =
+    abs(square(guess) - x) < 0.001                //> isGoodEnough: (guess: Double, x: Double)Boolean
+
+  //def sqrt(x: Double) = sqrtIter(1.0, x)
+  //sqrt(25)
+
+  // 4.5: Nested Functions
+
+  def sqrt(x: Double) = {
+    def sqrtIter(guess: Double): Double =
+      if (isGoodEnough(guess)) guess
+      else sqrtIter(improve(guess))
+    def improve(guess: Double) =
+      (guess + x / guess) / 2
+    def isGoodEnough(guess: Double) =
+      abs(square(guess) - x) < 0.001
+    sqrtIter(1.0)
+  }                                               //> sqrt: (x: Double)Double
+  sqrt(25)                                        //> res11: Double = 1.0
+
+  // 4.6: Tail Recursion
+
+  def gcd(a: Int, b: Int): Int = if (b == 0) a else gcd(b, a % b)
+                                                  //> gcd: (a: Int, b: Int)Int
+
+  gcd(21, 36)                                     //> res12: Int = 3
+
+}
\ No newline at end of file