about summary refs log tree commit diff
path: root/src/math/e_scalb.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/math/e_scalb.c')
-rw-r--r--src/math/e_scalb.c35
1 files changed, 35 insertions, 0 deletions
diff --git a/src/math/e_scalb.c b/src/math/e_scalb.c
new file mode 100644
index 00000000..cee2b44f
--- /dev/null
+++ b/src/math/e_scalb.c
@@ -0,0 +1,35 @@
+
+/* @(#)e_scalb.c 1.3 95/01/18 */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunSoft, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice 
+ * is preserved.
+ * ====================================================
+ */
+
+/*
+ * scalb(x, fn) is provide for
+ * passing various standard test suite. One 
+ * should use scalbn() instead.
+ */
+
+#include <math.h>
+#include "math_private.h"
+
+double
+scalb(double x, double fn)
+{
+        if (isnan(x)||isnan(fn)) return x*fn;
+        if (!isfinite(fn)) {
+            if(fn>0.0) return x*fn;
+            else       return x/(-fn);
+        }
+        if (rint(fn)!=fn) return (fn-fn)/(fn-fn);
+        if ( fn > 65000.0) return scalbn(x, 65000);
+        if (-fn > 65000.0) return scalbn(x,-65000);
+        return scalbn(x,(int)fn);
+}