asinh

float       asinhf( float arg );

double      asinh( double arg );

long double asinhl( long double arg );

#define asinh( arg )

Parameters

Return value

If no errors occur, the inverse hyperbolic sine of arg (sinh-1
(arg), or arsinh(arg)), is returned.

If a range error occurs due to underflow, the correct result (after rounding) is returned.

Error handling

Errors are reported as specified in math_errhandling.

If the implementation supports IEEE floating-point arithmetic (IEC 60559),

• if the argument is ±0 or ±∞, it is returned unmodified
• if the argument is NaN, NaN is returned

Notes

Although the C standard names this function "arc hyperbolic sine", the inverse functions of the hyperbolic functions are the area functions. Their argument is the area of a hyperbolic sector, not an arc. The correct name is "inverse hyperbolic sine" (used by POSIX) or "area hyperbolic sine".

Example

#include <stdio.h>
#include <math.h>
 
int main(void)
{
    printf("asinh(1) = %f\nasinh(-1) = %f\n", asinh(1), asinh(-1));
    // special values
    printf("asinh(+0) = %f\nasinh(-0) = %f\n", asinh(0.0), asinh(-0.0));
}

asinh(1) = 0.881374
asinh(-1) = -0.881374
asinh(+0) = 0.000000
asinh(-0) = -0.000000

References

• C11 standard (ISO/IEC 9899:2011):
  • 7.12.5.2 The asinh functions (p: 240-241)
  • 7.25 Type-generic math <tgmath.h> (p: 373-375)
  • F.10.2.2 The asinh functions (p: 520)
• C99 standard (ISO/IEC 9899:1999):
  • 7.12.5.2 The asinh functions (p: 221)
  • 7.22 Type-generic math <tgmath.h> (p: 335-337)
  • F.9.2.2 The asinh functions (p: 457)

See also

External links

Weisstein, Eric W. "Inverse Hyperbolic Sine." From MathWorld--A Wolfram Web Resource.