Trailing-Edge
-
PDP-10 Archives
-
SRI_NIC_PERM_FS_1_19910112
-
kcc-5/lib/math/sinh.c
There are 7 other files named sinh.c in the archive. Click here to see a list.
/*
* +++ NAME +++
*
* SINH Double precision hyperbolic sine
*
* +++ INDEX +++
*
* SINH
* machine independent routines
* math libraries
*
* +++ DESCRIPTION +++
*
* Returns double precision hyperbolic sine of double precision
* floating point number.
*
* +++ USAGE +++
*
* double sinh(x)
* double x;
*
* +++ REFERENCES +++
*
* Fortran IV plus user's guide, Digital Equipment Corp. pp B-5
*
* +++ RESTRICTIONS +++
*
* Inputs greater than LN(MAX_POS_DBLF) result in overflow.
* Inputs less than LN(MIN_POS_DBLF) result in underflow.
*
* For precision information refer to documentation of the
* floating point library routines called.
*
* +++ PROGRAMMER +++
*
* Fred Fish
* Goodyear Aerospace Corp, Arizona Div.
* (602) 932-7000 work
* (602) 894-6881 home
*
* Updated Dec 85 for inclusion in standard math library. This routine
* now conforms with the description of the sinh function as defined in
* Harbison & Steele's "C: A Reference Manual", section 11.3.22
*
* +++ INTERNALS +++
*
* Computes hyperbolic sine from:
*
* sinh(X) = 0.5 * (exp(X) - exp(-X))
*
* ---
*/
#include "math.h"
#include "errno.h"
double sinh(x)
double x;
{
if (x > LN_MAXPOSDBL) {
errno = ERANGE;
return MAX_POS_DBLF;
} else if (x < LN_MINPOSDBL) {
errno = ERANGE;
return MIN_POS_DBLF;
} else {
return 0.5 * (exp(x) - exp(-x));
}
}