atanh(), atanhf() inverse hyperbolic tangent function	Function
	SYNOPSIS DESCRIPTION PARAMETERS RETURN VALUES CONFORMANCE MULTITHREAD SAFETY LEVEL PORTING ISSUES AVAILABILITY SEE ALSO

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SYNOPSIS

#include <math.h>

double atanh(double x)

float atanhf(float x)

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DESCRIPTION

The atanh() and atanhf() functions compute the inverse hyperbolic tangent of the real argument x.

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PARAMETERS

x 

Is a value between -1.0 and 1.0, exclusive.

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RETURN VALUES

The atanh() function returns the inverse hyperbolic tangent.

If x is greater than 1.0 or x is NaN, then:

• if in IEEE mode, a value of NaN is returned.

• if in POSIX mode, a value of NaN is returned.

• if in SVID or XOPEN mode, NaN is returned and matherr() is called.

If the absolute value of x is 1.0, a value of infinity is returned. If in POSIX mode, errno is set to EDOM.

If x is NaN, atanh() returns NaN.

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CONFORMANCE

atanh(): UNIX 98

atanhf(): PTC MKS Toolkit UNIX APIs extension

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MULTITHREAD SAFETY LEVEL

MT-Safe.

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PORTING ISSUES

None.

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AVAILABILITY

PTC MKS Toolkit for Professional Developers
PTC MKS Toolkit for Professional Developers 64-Bit Edition
PTC MKS Toolkit for Enterprise Developers
PTC MKS Toolkit for Enterprise Developers 64-Bit Edition

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SEE ALSO

Functions:

acosh(), asinh(), exp(), math(), matherr()

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PTC MKS Toolkit 10.5 Documentation Build 40.