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Diffstat (limited to 'src/math/scalb.c')
-rw-r--r-- | src/math/scalb.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/src/math/scalb.c b/src/math/scalb.c new file mode 100644 index 00000000..7706e9cb --- /dev/null +++ b/src/math/scalb.c @@ -0,0 +1,34 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/e_scalb.c */ +/* + * ==================================================== + * 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 "libm.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); +} |