First commit.

1 files changed, 60 insertions, 0 deletions

diff --git a/tests/exec/mandelbrot.cpp b/tests/exec/mandelbrot.cpp
new file mode 100644
index 0000000..206b18b
--- /dev/null
+++ b/tests/exec/mandelbrot.cpp
@@ -0,0 +1,60 @@
+
+#include <iostream>
+
+/* arithmetique de virgule fixe
+   precision q = 8192 i.e. 13 bits pour la partie decimale */
+
+int add(int x, int y) {
+  return x + y;
+}
+int sub(int x, int y) {
+  return x - y;
+}
+int mul(int x, int y) {
+  int t = x * y;
+  return (t + 8192 / 2) / 8192;
+}
+int div(int x, int y) {
+  int t = x * 8192;
+  return (t + y / 2) / y;
+}
+int of_int(int x) {
+  return x * 8192;
+}
+
+int iter(int n, int a, int b, int xn, int yn) {
+  if (n == 100) return true;
+  int xn2 = mul(xn, xn);
+  int yn2 = mul(yn, yn);
+  if (add(xn2, yn2) > of_int(4)) return false;
+  return iter(n+1, a, b, add(sub(xn2, yn2), a),
+              add(mul(of_int(2), mul(xn, yn)), b));
+}
+
+int inside(int x, int y) {
+  return iter(0, x, y, of_int(0), of_int(0));
+}
+
+int main() {
+  int steps = 30;
+  int xmin = of_int(-2);
+  int xmax = of_int(1);
+  int deltax = div(sub(xmax, xmin), of_int(2 * steps));
+  int ymin = of_int(-1);
+  int ymax = of_int(1);
+  int deltay = div(sub(ymax, ymin), of_int(steps));
+  int i;
+  for (i = 0; i < steps; i++) {
+    int y = add(ymin, mul(of_int(i), deltay));
+    int j;
+    for (j = 0; j < 2 * steps; j++) {
+      int x = add(xmin, mul(of_int(j), deltax));
+      if (inside(x, y))
+        std::cout << "0";
+      else
+        std::cout << "1";
+    }
+    std::cout << "\n";
+  }
+}
+