.

Makefile

@@ -0,0 +1,15 @@
+CC?=cc
+
+all:
+	$(CC) -lm -o sqrt sqrt.c
+
+check: all
+	./sqrt
+
+debug:
+	$(CC) -g -lm -o sqrt sqrt.c
+	gdb ./sqrt
+
+bericht:
+	latexmk -pdf bericht.tex;
+

sqrt.c

@@ -1,52 +1,68 @@
 #include <stdio.h>
 #include <math.h>
 #include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
 
-/*
- *        s   1
- *         \ /
- *          +
- *          |   1
- *          \  /
- *           >>
- *           |
- *       s   x
- *        \ / \
- *        (/) |\
- *         |  | \
- *         \ /   \
- *          +     \
- *          |  1  |
- *          \  /  |
- *           >>   |
- *            |  /
- *            \ /
- *             -
- */
 typedef uint32_t u32;
 
-u32 heron_sqrt(u32 s, int* iterations) {
-  // x_0 = (s + 1) / 2
-  // without increment to avoid overflow for 0xffffffff
-  u32 x = s >> 1;
-  u32 old_x = x;
+void heron_sqrt(u32 *mem) {
+  int i;
+  for (i = 1; i <= mem[0]; i++){
+    u32 s = mem[i];
+    // x_0 = (s + 1) / 2
+    // without increment to avoid overflow for 0xffffffff
+    u32 x = s >> 1;
+    u32 old_x = x;
 
-  *iterations = 0; // statistic
-
-  if (x == 0) return 0;
-  while(1) {
-    (*iterations)++; // statistic
-    // x_{n + 1} = (x_n + (s / x_n)) / 2
-    x = (x >> 1) + ((s/x) >> 1);
-    if (old_x  <= x) {
-      return x;
+    if (x != 0) {
+      while(1) {
+        // x_{n + 1} = (x_n + (s / x_n)) / 2
+        x = (x >> 1) + ((s/x) >> 1);
+        printf("%d\n", x);
+        if (old_x <= x) {
+          mem[i] = x;
+          break;
+        }
+        old_x = x;
+      }
     }
-    old_x = x;
+    mem[i] = x;
   }
 }
 
+//void heron_sqrt2(u32 *mem) {
+//  int i = 1;
+//  while(i <= mem[0]) {
+//    u32 s = mem[i];
+//    // x_0 = (s + 1) / 2
+//    // without increment to avoid overflow for 0xffffffff
+//    u32 x = s >> 1;
+//    u32 old_x = x;
+//
+//    if (x != 0) {
+//      while(1) {
+//        // x_{n + 1} = (x_n + (s / x_n)) / 2
+//        //x = (x >> 1) + ((s/x) >> 1);
+//        x = (x / 2) + ((s/x) / 2);
+//        printf("%d\n", x);
+//        if (old_x == x) {
+//          mem[i] = x;
+//          break;
+//        }
+//        old_x = x;
+//      }
+//    }
+//    mem[i] = x;
+//    i++;
+//  }
+//}
+
 int main() {
-  u32 data[] = {0, 2, 4,
+  u32 data[] = {0,
+    1,
+    2,
+    4,
     1<<2,
     1<<3,
     1<<4,
@@ -62,26 +78,24 @@ int main() {
     1<<24, // 32 -  8 = 24
     1<<30,
     0xffffffff};
-  int iter = 0, i = 0;
-  for (i = 0; i < sizeof(data)/sizeof(int); i++) {
-    if (i != 0) printf("------\n");
+  const int length = sizeof(data)/sizeof(u32);
+  const int mem_size = sizeof(data) + sizeof(u32);
+  u32* mem = malloc(mem_size);
+  memcpy(mem, data, mem_size);
+  u32* mem2 = malloc(mem_size);
+  memcpy(mem2, data, mem_size);
+
+  mem[0] = length;
+  heron_sqrt(mem);
+  //heron_sqrt2(mem2);
+
+  int i = 0;
+  for (i = 0; i < length; i++) {
     printf("s = %u\n", data[i]);
 
     printf("sqrt(s)      = %f\n", sqrt(data[i]));
-    printf("heron_sqrt(s)   = %d (%d iterations)\n",
-        heron_sqrt(data[i], &iter), iter);
-
-    // 1/16 = 0.0625
-    u32 s8 = data[i] << 8;
-    printf("heron_sqrt8(s)  = %f (%d iterations)%s\n",
-        ((double) heron_sqrt(s8, &iter)) / 16,
-        iter, s8 == 0 ? " Out of range!" : "");
-
-    // 1/128 = 0.0078125
-    u32 s14 = data[i] << 14;
-    printf("heron_sqrt14(s) = %f (%d iterations)%s\n",
-        ((double) heron_sqrt(data[i]<<14, &iter)) / 128,
-        iter, s14 == 0 ? " Out of range!" : "");
+    printf("heron_sqrt(s)   = %d\n", mem[i]);
+    //printf("heron_sqrt2(s)   = %d\n", mem2[i]);
   }
   return 0;
 }