Import sources from 2011-03-30 iso image

1 files changed, 29 insertions, 0 deletions

diff --git a/sys/src/ape/lib/ap/math/hypot.c b/sys/src/ape/lib/ap/math/hypot.c
new file mode 100755
index 000000000..25457d8a9
--- /dev/null
+++ b/sys/src/ape/lib/ap/math/hypot.c
@@ -0,0 +1,29 @@
+#include <math.h>
+/*
+ * sqrt(a^2 + b^2)
+ *	(but carefully)
+ */
+
+double
+hypot(double a, double b)
+{
+	double t;
+
+	if(a < 0)
+		a = -a;
+	if(b < 0)
+		b = -b;
+	if(a > b) {
+		t = a;
+		a = b;
+		b = t;
+	}
+	if(b == 0) 
+		return 0;
+	a /= b;
+	/*
+	 * pathological overflow possible
+	 * in the next line.
+	 */
+	return b * sqrt(1 + a*a);
+}