1 2 /* @(#)s_copysign.c 5.1 93/09/24 */ 3 /* 4 * ==================================================== 5 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 6 * 7 * Developed at SunPro, a Sun Microsystems, Inc. business. 8 * Permission to use, copy, modify, and distribute this 9 * software is freely granted, provided that this notice 10 * is preserved. 11 * ==================================================== 12 */ 13 14 /* 15 FUNCTION 16 <<copysign>>, <<copysignf>>---sign of <[y]>, magnitude of <[x]> 17 18 INDEX 19 copysign 20 INDEX 21 copysignf 22 23 ANSI_SYNOPSIS 24 #include <math.h> 25 double copysign (double <[x]>, double <[y]>); 26 float copysignf (float <[x]>, float <[y]>); 27 28 TRAD_SYNOPSIS 29 #include <math.h> 30 double copysign (<[x]>, <[y]>) 31 double <[x]>; 32 double <[y]>; 33 34 float copysignf (<[x]>, <[y]>) 35 float <[x]>; 36 float <[y]>; 37 38 DESCRIPTION 39 <<copysign>> constructs a number with the magnitude (absolute value) 40 of its first argument, <[x]>, and the sign of its second argument, 41 <[y]>. 42 43 <<copysignf>> does the same thing; the two functions differ only in 44 the type of their arguments and result. 45 46 RETURNS 47 <<copysign>> returns a <<double>> with the magnitude of 48 <[x]> and the sign of <[y]>. 49 <<copysignf>> returns a <<float>> with the magnitude of 50 <[x]> and the sign of <[y]>. 51 52 PORTABILITY 53 <<copysign>> is not required by either ANSI C or the System V Interface 54 Definition (Issue 2). 55 56 */ 57 58 /* 59 * copysign(double x, double y) 60 * copysign(x,y) returns a value with the magnitude of x and 61 * with the sign bit of y. 62 */ 63 64 #include "fdlibm.h" 65 66 #ifndef _DOUBLE_IS_32BITS 67 68 #ifdef __STDC__ copysign(double x,double y)69 double copysign(double x, double y) 70 #else 71 double copysign(x,y) 72 double x,y; 73 #endif 74 { 75 uint32_t hx,hy; 76 GET_HIGH_WORD(hx,x); 77 GET_HIGH_WORD(hy,y); 78 SET_HIGH_WORD(x,(hx&0x7fffffff)|(hy&0x80000000)); 79 return x; 80 } 81 82 #endif /* _DOUBLE_IS_32BITS */ 83