langs a-z

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

@@ -0,0 +1,108 @@
+#import <stdio.h>
+#import <stdint.h>
+#import <stdlib.h>
+#import <string.h>
+#import <objc/Object.h>
+
+// this class exists to return a result between two
+// vectors: if vectors have different "size", valid
+// must be NO
+@interface VResult : Object
+{
+ @private
+  double value;
+  BOOL valid;
+}
++(id)new: (double)v isValid: (BOOL)y;
+-(id)init: (double)v isValid: (BOOL)y;
+-(BOOL)isValid;
+-(double)value;
+@end
+
+@implementation VResult
++(id)new: (double)v isValid: (BOOL)y
+{
+  id s = [super new];
+  [s init: v isValid: y];
+  return s;
+}
+-(id)init: (double)v isValid: (BOOL)y
+{
+  value = v;
+  valid = y;
+  return self;
+}
+-(BOOL)isValid { return valid; }
+-(double)value { return value; }
+@end
+
+
+@interface RCVector : Object
+{
+ @private
+  double *vec;
+  uint32_t size;
+}
++(id)newWithArray: (double *)v ofLength: (uint32_t)l;
+-(id)initWithArray: (double *)v ofLength: (uint32_t)l;
+-(VResult *)dotProductWith: (RCVector *)v;
+-(uint32_t)size;
+-(double *)array;
+-(void)free;
+@end
+
+@implementation RCVector
++(id)newWithArray: (double *)v ofLength: (uint32_t)l
+{
+  id s = [super new];
+  [s initWithArray: v ofLength: l];
+  return s;
+}
+-(id)initWithArray: (double *)v ofLength: (uint32_t)l
+{
+  size = l;
+  vec = malloc(sizeof(double) * l);
+  if ( vec != NULL ) {
+    memcpy(vec, v, sizeof(double)*l);
+    return self;
+  }
+  [super free];
+  return nil;
+}
+-(void)free
+{
+  free(vec);
+  [super free];
+}
+-(uint32_t)size { return size; }
+-(double *)array { return vec; }
+-(VResult *)dotProductWith: (RCVector *)v
+{
+  double r = 0.0;
+  uint32_t i, s;
+  double *v1;
+  if ( [self size] != [v size] ) return [VResult new: r isValid: NO];
+  s = [self size];
+  v1 = [v array];
+  for(i = 0; i < s; i++) {
+    r += vec[i] * v1[i];
+  }
+  return [VResult new: r isValid: YES];
+}
+@end
+
+double val1[] = { 1, 3, -5 };
+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");
+  }
+  return 0;
+}