| #include "cephes_mconf.h" | |
| #ifndef _SET_ERRNO | |
| #define _SET_ERRNO(x) | |
| #endif | |
| long double coshl(x) | |
| long double x; | |
| { | |
| long double y; | |
| #ifdef NANS | |
| if( isnanl(x) ) | |
| { | |
| _SET_ERRNO(EDOM); | |
| return(x); | |
| } | |
| #endif | |
| if( x < 0 ) | |
| x = -x; | |
| if( x > (MAXLOGL + LOGE2L) ) | |
| { | |
| mtherr( "coshl", OVERFLOW ); | |
| _SET_ERRNO(ERANGE); | |
| #ifdef INFINITIES | |
| return( INFINITYL ); | |
| #else | |
| return( MAXNUML ); | |
| #endif | |
| } | |
| if( x >= (MAXLOGL - LOGE2L) ) | |
| { | |
| y = expl(0.5L * x); | |
| y = (0.5L * y) * y; | |
| return(y); | |
| } | |
| y = expl(x); | |
| y = 0.5L * (y + 1.0L / y); | |
| return( y ); | |
| } |