1 files changed, 60 insertions, 0 deletions
diff --git a/ic-reals-6.3/tests/iterate.c b/ic-reals-6.3/tests/iterate.c
new file mode 100644
index 0000000..89c3f07
--- /dev/null
+++ b/ic-reals-6.3/tests/iterate.c
@@ -0,0 +1,60 @@
+#include <stdio.h>
+#include "real.h"
+#include "real-impl.h"
+
+main(int argc, char *argv[])
+{
+	Real x, y;
+	double f;
+	Real makeRealSignCNQInt(Sign, char *, int, int, int);
+	Real iterate(Real, int);
+	int niters;
+
+	MyName = argv[0];
+
+	if (argc != 8) {
+		fprintf(stderr, "%s <sign> <c> <n> <a> <b> <n-iters> <ndigits>\n",
+				MyName);
+		exit(1);
+	}
+
+	initReals();
+
+	y = makeRealSignCNQInt(
+				atoi(argv[1]),  /* sign */
+				argv[2],		/* c */
+				atoi(argv[3]),  /* n */
+				atoi(argv[4]),  /* a */
+				atoi(argv[5])); /* b */
+
+	niters = atoi(argv[6]);
+
+	print_R_Dec(y, atoi(argv[7]));
+	printf("\n");
+
+	x = iterate(y, niters);
+
+	print_R_Dec(x, atoi(argv[7]));
+	printf("\n");
+}
+
+/*
+ * Iterates the function f(x) = 4x(1-x)
+ */
+Real
+iterate(Real x, int n)
+{
+	Real p, q, r; 
+
+	if (n > 0) {
+		r = iterate(x, n - 1);
+		p = mul_R_Int(r, 4);
+		q = sub_Int_R(1, r);
+		r = mul_R_R(p, q);
+		if (n > 15)
+			r = makeStream(r);
+		return r;
+	}
+	else
+		return x;
+}