1 2 /* 3 * ==================================================== 4 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 5 * 6 * Developed at SunSoft, a Sun Microsystems, Inc. business. 7 * Permission to use, copy, modify, and distribute this 8 * software is freely granted, provided that this notice 9 * is preserved. 10 * ==================================================== 11 */ 12 13 #include <sys/cdefs.h> 14 /* 15 * scalb(x, fn) is provide for 16 * passing various standard test suite. One 17 * should use scalbn() instead. 18 */ 19 20 #include "math.h" 21 #include "math_private.h" 22 23 #ifdef _SCALB_INT 24 double 25 scalb(double x, int fn) 26 #else 27 double 28 scalb(double x, double fn) 29 #endif 30 { 31 #ifdef _SCALB_INT 32 return scalbn(x,fn); 33 #else 34 if (isnan(x)||isnan(fn)) return x*fn; 35 if (!finite(fn)) { 36 if(fn>0.0) return x*fn; 37 else return x/(-fn); 38 } 39 if (rint(fn)!=fn) return (fn-fn)/(fn-fn); 40 if ( fn > 65000.0) return scalbn(x, 65000); 41 if (-fn > 65000.0) return scalbn(x,-65000); 42 return scalbn(x,(int)fn); 43 #endif 44 } 45