March 2014 update

Task/Dot-product/D/dot-product-2.d

@@ -1,9 +1,8 @@
 void main() {
-    import std.stdio, std.range, std.algorithm;
+    import std.stdio, std.algorithm;
 
     double[3] a = [1.0, 3.0, -5.0];
     double[3] b = [4.0, -2.0, -1.0];
-    double[3] c;
-    c[] = a[] * b[];
-    c.reduce!q{a + b}.writeln;
+    double[3] c = a[] * b[];
+    c[].sum.writeln;
 }

Task/Dot-product/Dart/dot-product.dart

@@ -0,0 +1,16 @@
+num dot(List<num> A, List<num> B){
+  if (A.length != B.length){
+    throw new Exception('Vectors must be of equal size');
+  }
+  num result = 0;
+  for (int i = 0; i < A.length; i++){
+    result += A[i] * B[i];
+  }
+  return result;
+}
+
+void main(){
+  var l = [1,3,-5];
+  var k = [4,-2,-1];
+  print(dot(l,k));
+}

Task/Dot-product/Maple/dot-product-1.maple

@@ -0,0 +1 @@
+<1,2,3> . <4,5,6>

Task/Dot-product/Maple/dot-product-2.maple

@@ -0,0 +1 @@
+Array([1,2,3]) . Array([4,5,6])

Task/Dot-product/Maple/dot-product-3.maple

@@ -0,0 +1 @@
+LinearAlgebra( <1,2,3>, <4,5,6> )

Task/Dot-product/Maple/dot-product-4.maple

@@ -0,0 +1 @@
+LinearAlgebra( Array([1,2,3]), Array([4,5,6]) )

Task/Dot-product/Maple/dot-product-5.maple

@@ -0,0 +1 @@
+LinearAlgebra([1,2,3], [4,5,6] )

Task/Dot-product/Objective-C/dot-product.m

@@ -2,34 +2,34 @@
 #import <stdint.h>
 #import <stdlib.h>
 #import <string.h>
-#import <objc/Object.h>
+#import <Foundation/Foundation.h>
 
 // this class exists to return a result between two
 // vectors: if vectors have different "size", valid
 // must be NO
-@interface VResult : Object
+@interface VResult : NSObject
 {
  @private
   double value;
   BOOL valid;
 }
-+(id)new: (double)v isValid: (BOOL)y;
--(id)init: (double)v isValid: (BOOL)y;
++(instancetype)new: (double)v isValid: (BOOL)y;
+-(instancetype)init: (double)v isValid: (BOOL)y;
 -(BOOL)isValid;
 -(double)value;
 @end
 
 @implementation VResult
-+(id)new: (double)v isValid: (BOOL)y
++(instancetype)new: (double)v isValid: (BOOL)y
 {
-  id s = [super new];
-  [s init: v isValid: y];
-  return s;
+  return [[self alloc] init: v isValid: y];
 }
--(id)init: (double)v isValid: (BOOL)y
+-(instancetype)init: (double)v isValid: (BOOL)y
 {
-  value = v;
-  valid = y;
+  if ((self == [super init])) {
+    value = v;
+    valid = y;
+  }
   return self;
 }
 -(BOOL)isValid { return valid; }
@@ -37,14 +37,14 @@
 @end
 
 
-@interface RCVector : Object
+@interface RCVector : NSObject
 {
  @private
   double *vec;
   uint32_t size;
 }
-+(id)newWithArray: (double *)v ofLength: (uint32_t)l;
--(id)initWithArray: (double *)v ofLength: (uint32_t)l;
++(instancetype)newWithArray: (double *)v ofLength: (uint32_t)l;
+-(instancetype)initWithArray: (double *)v ofLength: (uint32_t)l;
 -(VResult *)dotProductWith: (RCVector *)v;
 -(uint32_t)size;
 -(double *)array;
@@ -52,27 +52,24 @@
 @end
 
 @implementation RCVector
-+(id)newWithArray: (double *)v ofLength: (uint32_t)l
++(instancetype)newWithArray: (double *)v ofLength: (uint32_t)l
 {
-  id s = [super new];
-  [s initWithArray: v ofLength: l];
-  return s;
+  return [[self alloc] initWithArray: v ofLength: l];
 }
--(id)initWithArray: (double *)v ofLength: (uint32_t)l
+-(instancetype)initWithArray: (double *)v ofLength: (uint32_t)l
 {
-  size = l;
-  vec = malloc(sizeof(double) * l);
-  if ( vec != NULL ) {
+  if ((self = [super init])) {
+    size = l;
+    vec = malloc(sizeof(double) * l);
+    if ( vec == NULL )
+      return nil;
     memcpy(vec, v, sizeof(double)*l);
-    return self;
   }
-  [super free];
-  return nil;
+  return self;
 }
--(void)free
+-(void)dealloc
 {
   free(vec);
-  [super free];
 }
 -(uint32_t)size { return size; }
 -(double *)array { return vec; }
@@ -96,13 +93,15 @@ double val2[] = { 4,-2, -1 };
 
 int main()
 {
-  RCVector *v1 = [RCVector newWithArray: val1 ofLength: sizeof(val1)/sizeof(double)];
-  RCVector *v2 = [RCVector newWithArray: val2 ofLength: sizeof(val1)/sizeof(double)];
-  VResult *r = [v1 dotProductWith: v2];
-  if ( [r isValid] ) {
-    printf("%lf\n", [r value]);
-  } else {
-    fprintf(stderr, "length of vectors differ\n");
+  @autoreleasepool {
+    RCVector *v1 = [RCVector newWithArray: val1 ofLength: sizeof(val1)/sizeof(double)];
+    RCVector *v2 = [RCVector newWithArray: val2 ofLength: sizeof(val1)/sizeof(double)];
+    VResult *r = [v1 dotProductWith: v2];
+    if ( [r isValid] ) {
+      printf("%lf\n", [r value]);
+    } else {
+      fprintf(stderr, "length of vectors differ\n");
+    }
   }
   return 0;
 }

Task/Dot-product/Scala/dot-product.scala

@@ -1,12 +1,18 @@
+import scala.language.postfixOps
+import scala.language.implicitConversions
+
 class Dot[T](v1: Seq[T])(implicit n: Numeric[T]) {
-  import n._
+  import n._ // import * operator
   def dot(v2: Seq[T]) = {
-    require(v1.length == v2.length)
-    v1 zip v2 map Function.tupled(_*_) sum
+    require(v1.size == v2.size)
+    v1 zip v2 map Function.tupled(_ * _) sum
   }
 }
 
-implicit def toDot[T : Numeric](v1: Seq[T]) = new Dot(v1)
-val v1 = List(1, 3, -5)
-val v2 = List(4, -2, -1)
-println(v1 dot v2)
+object Main extends App {
+  implicit def toDot[T: Numeric](v1: Seq[T]) = new Dot(v1)
+
+  val v1 = List(1, 3, -5)
+  val v2 = List(4, -2, -1)
+  println(v1 dot v2)
+}