e_scalbf.c revision 1.5
1/* e_scalbf.c -- float version of e_scalb.c. 2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. 3 */ 4 5/* 6 * ==================================================== 7 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 8 * 9 * Developed at SunPro, a Sun Microsystems, Inc. business. 10 * Permission to use, copy, modify, and distribute this 11 * software is freely granted, provided that this notice 12 * is preserved. 13 * ==================================================== 14 */ 15 16#include "math.h" 17#include "math_private.h" 18 19#ifdef _SCALB_INT 20float 21scalbf(float x, int fn) 22{ 23 return scalbnf(x,fn); 24} 25 26#else 27 28float 29scalbf(float x, float fn) 30{ 31 if (isnan(x)||isnan(fn)) return x*fn; 32 if (!isfinite(fn)) { 33 if(fn>(float)0.0) return x*fn; 34 else return x/(-fn); 35 } 36 if (rintf(fn)!=fn) return (fn-fn)/(fn-fn); 37 if ( fn > (float)65000.0) return scalbnf(x, 65000); 38 if (-fn > (float)65000.0) return scalbnf(x,-65000); 39 return scalbnf(x,(int)fn); 40} 41#endif 42