hw 4

1 files changed, 42 insertions, 42 deletions

diff --git a/src/vector.c b/src/vector.c
index a7ff783..4a6250c 100644
--- a/src/vector.c
+++ b/src/vector.c
@@ -2,30 +2,18 @@
 #include <assert.h>
 #include <float.h>
 #include <math.h>
-#include <string.h>
 #include <stdio.h>
+#include <string.h>
 
-double l2_norm(Array_double *v) {
-  double norm = 0;
-  for (size_t i = 0; i < v->size; ++i)
-    norm += v->data[i] * v->data[i];
-  return sqrt(norm);
-}
+Array_double *add_v(Array_double *v1, Array_double *v2) {
+  assert(v1->size == v2->size);
 
-double l1_norm(Array_double *v) {
-  double sum = 0;
-  for (size_t i = 0; i < v->size; ++i)
-    sum += fabs(v->data[i]);
+  Array_double *sum = copy_vector(v1);
+  for (size_t i = 0; i < v1->size; i++)
+    sum->data[i] += v2->data[i];
   return sum;
 }
 
-double linf_norm(Array_double *v) {
-  double max = -DBL_MAX;
-  for (size_t i = 0; i < v->size; ++i)
-    max = c_max(v->data[i], max);
-  return max;
-}
-
 Array_double *minus_v(Array_double *v1, Array_double *v2) {
   assert(v1->size == v2->size);
 
@@ -35,13 +23,6 @@ Array_double *minus_v(Array_double *v1, Array_double *v2) {
   return sub;
 }
 
-double sum_v(Array_double *v) {
-  double sum = 0;
-  for (size_t i = 0; i < v->size; i++)
-    sum += v->data[i];
-  return sum;
-}
-
 Array_double *scale_v(Array_double *v, double m) {
   Array_double *copy = copy_vector(v);
   for (size_t i = 0; i < v->size; i++)
@@ -49,16 +30,29 @@ Array_double *scale_v(Array_double *v, double m) {
   return copy;
 }
 
-Array_double *add_v(Array_double *v1, Array_double *v2) {
-  assert(v1->size == v2->size);
-
-  Array_double *sum = copy_vector(v1);
-  for (size_t i = 0; i < v1->size; i++)
-    sum->data[i] += v2->data[i];
+double l1_norm(Array_double *v) {
+  double sum = 0;
+  for (size_t i = 0; i < v->size; ++i)
+    sum += fabs(v->data[i]);
   return sum;
 }
 
-double dot_v(Array_double *v1, Array_double *v2) {
+double l2_norm(Array_double *v) {
+  double norm = 0;
+  for (size_t i = 0; i < v->size; ++i)
+    norm += v->data[i] * v->data[i];
+  return sqrt(norm);
+}
+
+double linf_norm(Array_double *v) {
+  assert(v->size > 0);
+  double max = v->data[0];
+  for (size_t i = 0; i < v->size; ++i)
+    max = c_max(v->data[i], max);
+  return max;
+}
+
+double v_dot_v(Array_double *v1, Array_double *v2) {
   assert(v1->size == v2->size);
 
   double dot = 0;
@@ -67,25 +61,24 @@ double dot_v(Array_double *v1, Array_double *v2) {
   return dot;
 }
 
-double l2_distance(Array_double *v1, Array_double *v2) {
+double vector_distance(Array_double *v1, Array_double *v2,
+                       double (*norm)(Array_double *)) {
   Array_double *minus = minus_v(v1, v2);
-  double dist = l2_norm(minus);
+  double dist = (*norm)(minus);
   free(minus);
   return dist;
 }
 
 double l1_distance(Array_double *v1, Array_double *v2) {
-  Array_double *minus = minus_v(v1, v2);
-  double dist = l1_norm(minus);
-  free(minus);
-  return dist;
+  return vector_distance(v1, v2, &l1_norm);
+}
+
+double l2_distance(Array_double *v1, Array_double *v2) {
+  return vector_distance(v1, v2, &l2_norm);
 }
 
 double linf_distance(Array_double *v1, Array_double *v2) {
-  Array_double *minus = minus_v(v1, v2);
-  double dist = linf_norm(minus);
-  free(minus);
-  return dist;
+  return vector_distance(v1, v2, &linf_norm);
 }
 
 Array_double *copy_vector(Array_double *v) {
@@ -115,3 +108,10 @@ void format_vector_into(Array_double *v, char *s) {
   }
   strcat(s, "\n");
 }
+
+double sum_v(Array_double *v) {
+  double sum = 0;
+  for (size_t i = 0; i < v->size; i++)
+    sum += v->data[i];
+  return sum;
+}