| [ CnUnix ] in KIDS 글 쓴 이(By): darkman (아랑타불) 날 짜 (Date): 2004년 7월 16일 금요일 오후 11시 13분 08초 제 목(Title): Re: [Q]켅99에서 복소수 This is about cabs and friends on IRIX, but even so, not at all: IRIX 6.5.18 and up have C99 support, which is done like this: <internal/math_core.h> (included from <math.h>) has #if !defined(__c99) struct __cabs_s { double a,b; }; extern double cabs(struct __cabs_s); [...] #endif and <complex.h> has /* C99: 7.3.8.1 */ /* c89 also had functions cabs, cabsf and cabsl with the following * prototypes. * * double cabs (struct { double a,b; } z); * float cabsf (struct { float a,b; } z); * long double cabsl (struct { long double a,b; } z); * * As the passing of structs by value is different from passing * complex by value for the float and long double cases, the following * changes are being done to the C99 functions so as to maintain * backwards compatibility. * * For the C99 functions we provide static definitions of these, * which in turn call the corresponding library functions with a __c99_ * prefix. * * There are two drawbacks of this approach * * 1. As each compilation will get its own copy of these functions, * any program which relies on the address of these functions being * unique will fail. * * 2. If the user rolls his own version of these functions, they will * never get invoked, and to get around this problem, the user * should be able to disable the generation of these static functions. * This is achieved by adding -D_C99_CABS_USER_DEFINED to the commandline. */ extern double __c99_cabs (double complex); extern float __c99_cabsf (float complex); extern long double __c99_cabsl (long double complex); #pragma optional __c99_cabs #pragma optional __c99_cabsf #pragma optional __c99_cabsl #ifdef _C99_CABS_USER_DEFINED extern double cabs (double complex); extern float cabsf (float complex); extern long double cabsl (long double complex); #else static inline double cabs (double complex z) {return __c99_cabs(z); } static inline float cabsf (float complex z) {return __c99_cabsf(z);} static inline long double cabsl (long double complex z) {return __c99_cabsl(z);} #endif /* _C99_CABS_USER_DEFINED */ 인터넷에 보니 이런글도 |