Initial commit

Compute if a number is in Mandelbrot set.
Print it to the terminal.

1 files changed, 54 insertions, 0 deletions

diff --git a/mandelbrot.c b/mandelbrot.c
new file mode 100644
index 0000000..053ce70
--- /dev/null
+++ b/mandelbrot.c
@@ -0,0 +1,54 @@
+#include <stdio.h>
+#include <math.h>
+#include <complex.h>
+
+#define LO -1.7
+#define HI 1.7
+#define AXIS_DIV 46.0
+#define AXIS_STEP ((HI - LO) / AXIS_DIV)
+
+#define MAX_ITERATION 1000
+#define _INFINITY 1000
+
+#define IN_CHAR '*'
+#define OUT_CHAR ' '
+
+/*
+#define SQUARE(x) (pow((x), 2))
+#define SQUARE_CML(z) (SQUARE(creal(z)) - SQUARE(cimag(z)) + 2 * creal(z) * cimag(z) * I)
+
+double magnitude(double complex z)
+{
+    return sqrt(SQUARE(creal(z)) + SQUARE(cimag(z)));
+}
+*/
+
+double mandelbrot_in_set(double complex c)
+{
+    int i;
+    double complex z = 0;
+    for (i = 0; i < MAX_ITERATION; i++)
+    {
+        z = cpow(z, 2) + c;
+        if (cabs(z) > _INFINITY)
+            return 0;
+    }
+    return 1;
+}
+
+void mandelbrot_print(void)
+{
+    for (double i = LO; i < HI; i += AXIS_STEP)
+    {
+        for (double r = LO; r < HI; r += AXIS_STEP)
+        {
+            if (mandelbrot_in_set(r + i * I))
+                putchar(IN_CHAR);
+            else
+                putchar(OUT_CHAR);
+            putchar(' ');
+        }
+        putchar('\n');
+    }
+}
+